1 /* 2 * Copyright (c) 1997, 2021, Oracle and/or its affiliates. All rights reserved. 3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. 4 * 5 * This code is free software; you can redistribute it and/or modify it 6 * under the terms of the GNU General Public License version 2 only, as 7 * published by the Free Software Foundation. 8 * 9 * This code is distributed in the hope that it will be useful, but WITHOUT 10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 12 * version 2 for more details (a copy is included in the LICENSE file that 13 * accompanied this code). 14 * 15 * You should have received a copy of the GNU General Public License version 16 * 2 along with this work; if not, write to the Free Software Foundation, 17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. 18 * 19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA 20 * or visit www.oracle.com if you need additional information or have any 21 * questions. 22 * 23 */ 24 25 #ifndef SHARE_RUNTIME_GLOBALS_HPP 26 #define SHARE_RUNTIME_GLOBALS_HPP 27 28 #include "compiler/compiler_globals_pd.hpp" 29 #include "runtime/globals_shared.hpp" 30 #include "utilities/align.hpp" 31 #include "utilities/globalDefinitions.hpp" 32 #include "utilities/macros.hpp" 33 #include CPU_HEADER(globals) 34 #include OS_HEADER(globals) 35 #include OS_CPU_HEADER(globals) 36 37 // develop flags are settable / visible only during development and are constant in the PRODUCT version 38 // product flags are always settable / visible 39 // notproduct flags are settable / visible only during development and are not declared in the PRODUCT version 40 // develop_pd/product_pd flags are the same as develop/product, except that their default values 41 // are specified in platform-dependent header files. 42 43 // Flags must be declared with the following number of parameters: 44 // non-pd flags: 45 // (type, name, default_value, doc), or 46 // (type, name, default_value, extra_attrs, doc) 47 // pd flags: 48 // (type, name, doc), or 49 // (type, name, extra_attrs, doc) 50 51 // A flag must be declared with one of the following types: 52 // bool, int, uint, intx, uintx, size_t, ccstr, ccstrlist, double, or uint64_t. 53 // The type "ccstr" and "ccstrlist" are an alias for "const char*" and is used 54 // only in this file, because the macrology requires single-token type names. 55 56 // The optional extra_attrs parameter may have one of the following values: 57 // DIAGNOSTIC, EXPERIMENTAL, or MANAGEABLE. Currently extra_attrs can be used 58 // only with product/product_pd flags. 59 // 60 // DIAGNOSTIC options are not meant for VM tuning or for product modes. 61 // They are to be used for VM quality assurance or field diagnosis 62 // of VM bugs. They are hidden so that users will not be encouraged to 63 // try them as if they were VM ordinary execution options. However, they 64 // are available in the product version of the VM. Under instruction 65 // from support engineers, VM customers can turn them on to collect 66 // diagnostic information about VM problems. To use a VM diagnostic 67 // option, you must first specify +UnlockDiagnosticVMOptions. 68 // (This master switch also affects the behavior of -Xprintflags.) 69 // 70 // EXPERIMENTAL flags are in support of features that are not 71 // part of the officially supported product, but are available 72 // for experimenting with. They could, for example, be performance 73 // features that may not have undergone full or rigorous QA, but which may 74 // help performance in some cases and released for experimentation 75 // by the community of users and developers. This flag also allows one to 76 // be able to build a fully supported product that nonetheless also 77 // ships with some unsupported, lightly tested, experimental features. 78 // Like the UnlockDiagnosticVMOptions flag above, there is a corresponding 79 // UnlockExperimentalVMOptions flag, which allows the control and 80 // modification of the experimental flags. 81 // 82 // Nota bene: neither diagnostic nor experimental options should be used casually, 83 // and they are not supported on production loads, except under explicit 84 // direction from support engineers. 85 // 86 // MANAGEABLE flags are writeable external product flags. 87 // They are dynamically writeable through the JDK management interface 88 // (com.sun.management.HotSpotDiagnosticMXBean API) and also through JConsole. 89 // These flags are external exported interface (see CCC). The list of 90 // manageable flags can be queried programmatically through the management 91 // interface. 92 // 93 // A flag can be made as "manageable" only if 94 // - the flag is defined in a CCC as an external exported interface. 95 // - the VM implementation supports dynamic setting of the flag. 96 // This implies that the VM must *always* query the flag variable 97 // and not reuse state related to the flag state at any given time. 98 // - you want the flag to be queried programmatically by the customers. 99 // 100 101 // 102 // range is a macro that will expand to min and max arguments for range 103 // checking code if provided - see jvmFlagLimit.hpp 104 // 105 // constraint is a macro that will expand to custom function call 106 // for constraint checking if provided - see jvmFlagLimit.hpp 107 108 // Default and minimum StringTable and SymbolTable size values 109 // Must be powers of 2 110 const size_t defaultStringTableSize = NOT_LP64(1024) LP64_ONLY(65536); 111 const size_t minimumStringTableSize = 128; 112 const size_t defaultSymbolTableSize = 32768; // 2^15 113 const size_t minimumSymbolTableSize = 1024; 114 115 #ifdef _LP64 116 #define LP64_RUNTIME_FLAGS(develop, \ 117 develop_pd, \ 118 product, \ 119 product_pd, \ 120 notproduct, \ 121 range, \ 122 constraint) \ 123 \ 124 product(bool, UseCompressedOops, false, \ 125 "Use 32-bit object references in 64-bit VM. " \ 126 "lp64_product means flag is always constant in 32 bit VM") \ 127 \ 128 product(bool, UseCompressedClassPointers, false, \ 129 "Use 32-bit class pointers in 64-bit VM. " \ 130 "lp64_product means flag is always constant in 32 bit VM") \ 131 \ 132 product(bool, UseCompactObjectHeaders, false, EXPERIMENTAL, \ 133 "Use 64-bit object headers instead of 96-bit headers") \ 134 \ 135 product(intx, ObjectAlignmentInBytes, 8, \ 136 "Default object alignment in bytes, 8 is minimum") \ 137 range(8, 256) \ 138 constraint(ObjectAlignmentInBytesConstraintFunc, AtParse) 139 140 #else 141 // !_LP64 142 143 #define LP64_RUNTIME_FLAGS(develop, \ 144 develop_pd, \ 145 product, \ 146 product_pd, \ 147 notproduct, \ 148 range, \ 149 constraint) 150 const bool UseCompressedOops = false; 151 const bool UseCompressedClassPointers = false; 152 const bool UseCompactObjectHeaders = false; 153 const intx ObjectAlignmentInBytes = 8; 154 155 #endif // _LP64 156 157 #define RUNTIME_FLAGS(develop, \ 158 develop_pd, \ 159 product, \ 160 product_pd, \ 161 notproduct, \ 162 range, \ 163 constraint) \ 164 \ 165 notproduct(bool, CheckCompressedOops, true, \ 166 "Generate checks in encoding/decoding code in debug VM") \ 167 \ 168 product(uintx, HeapSearchSteps, 3 PPC64_ONLY(+17), \ 169 "Heap allocation steps through preferred address regions to find" \ 170 " where it can allocate the heap. Number of steps to take per " \ 171 "region.") \ 172 range(1, max_uintx) \ 173 \ 174 product(uint, HandshakeTimeout, 0, DIAGNOSTIC, \ 175 "If nonzero set a timeout in milliseconds for handshakes") \ 176 \ 177 product(bool, AlwaysSafeConstructors, false, EXPERIMENTAL, \ 178 "Force safe construction, as if all fields are final.") \ 179 \ 180 product(bool, UnlockDiagnosticVMOptions, trueInDebug, DIAGNOSTIC, \ 181 "Enable normal processing of flags relating to field diagnostics")\ 182 \ 183 product(bool, UnlockExperimentalVMOptions, false, EXPERIMENTAL, \ 184 "Enable normal processing of flags relating to experimental " \ 185 "features") \ 186 \ 187 product(bool, JavaMonitorsInStackTrace, true, \ 188 "Print information about Java monitor locks when the stacks are " \ 189 "dumped") \ 190 \ 191 product_pd(bool, UseLargePages, \ 192 "Use large page memory") \ 193 \ 194 product_pd(bool, UseLargePagesIndividualAllocation, \ 195 "Allocate large pages individually for better affinity") \ 196 \ 197 develop(bool, LargePagesIndividualAllocationInjectError, false, \ 198 "Fail large pages individual allocation") \ 199 \ 200 product(bool, UseNUMA, false, \ 201 "Use NUMA if available") \ 202 \ 203 product(bool, UseNUMAInterleaving, false, \ 204 "Interleave memory across NUMA nodes if available") \ 205 \ 206 product(size_t, NUMAInterleaveGranularity, 2*M, \ 207 "Granularity to use for NUMA interleaving on Windows OS") \ 208 constraint(NUMAInterleaveGranularityConstraintFunc, AtParse) \ 209 \ 210 product(uintx, NUMAChunkResizeWeight, 20, \ 211 "Percentage (0-100) used to weight the current sample when " \ 212 "computing exponentially decaying average for " \ 213 "AdaptiveNUMAChunkSizing") \ 214 range(0, 100) \ 215 \ 216 product(size_t, NUMASpaceResizeRate, 1*G, \ 217 "Do not reallocate more than this amount per collection") \ 218 range(0, max_uintx) \ 219 \ 220 product(bool, UseAdaptiveNUMAChunkSizing, true, \ 221 "Enable adaptive chunk sizing for NUMA") \ 222 \ 223 product(bool, NUMAStats, false, \ 224 "Print NUMA stats in detailed heap information") \ 225 \ 226 product(uintx, NUMAPageScanRate, 256, \ 227 "Maximum number of pages to include in the page scan procedure") \ 228 range(0, max_uintx) \ 229 \ 230 product(bool, UseAES, false, \ 231 "Control whether AES instructions are used when available") \ 232 \ 233 product(bool, UseFMA, false, \ 234 "Control whether FMA instructions are used when available") \ 235 \ 236 product(bool, UseSHA, false, \ 237 "Control whether SHA instructions are used when available") \ 238 \ 239 product(bool, UseGHASHIntrinsics, false, DIAGNOSTIC, \ 240 "Use intrinsics for GHASH versions of crypto") \ 241 \ 242 product(bool, UseBASE64Intrinsics, false, \ 243 "Use intrinsics for java.util.Base64") \ 244 \ 245 product(size_t, LargePageSizeInBytes, 0, \ 246 "Maximum large page size used (0 will use the default large " \ 247 "page size for the environment as the maximum)") \ 248 range(0, max_uintx) \ 249 \ 250 product(size_t, LargePageHeapSizeThreshold, 128*M, \ 251 "Use large pages if maximum heap is at least this big") \ 252 range(0, max_uintx) \ 253 \ 254 product(bool, ForceTimeHighResolution, false, \ 255 "Using high time resolution (for Win32 only)") \ 256 \ 257 develop(bool, TracePcPatching, false, \ 258 "Trace usage of frame::patch_pc") \ 259 \ 260 develop(bool, TraceRelocator, false, \ 261 "Trace the bytecode relocator") \ 262 \ 263 \ 264 product(bool, SafepointALot, false, DIAGNOSTIC, \ 265 "Generate a lot of safepoints. This works with " \ 266 "GuaranteedSafepointInterval") \ 267 \ 268 product(bool, HandshakeALot, false, DIAGNOSTIC, \ 269 "Generate a lot of handshakes. This works with " \ 270 "GuaranteedSafepointInterval") \ 271 \ 272 product_pd(bool, BackgroundCompilation, \ 273 "A thread requesting compilation is not blocked during " \ 274 "compilation") \ 275 \ 276 product(bool, MethodFlushing, true, \ 277 "Reclamation of zombie and not-entrant methods") \ 278 \ 279 develop(bool, VerifyStack, false, \ 280 "Verify stack of each thread when it is entering a runtime call") \ 281 \ 282 product(bool, ForceUnreachable, false, DIAGNOSTIC, \ 283 "Make all non code cache addresses to be unreachable by " \ 284 "forcing use of 64bit literal fixups") \ 285 \ 286 develop(bool, TraceDerivedPointers, false, \ 287 "Trace traversal of derived pointers on stack") \ 288 \ 289 notproduct(bool, TraceCodeBlobStacks, false, \ 290 "Trace stack-walk of codeblobs") \ 291 \ 292 notproduct(bool, PrintRewrites, false, \ 293 "Print methods that are being rewritten") \ 294 \ 295 product(bool, UseInlineCaches, true, \ 296 "Use Inline Caches for virtual calls ") \ 297 \ 298 product(bool, InlineArrayCopy, true, DIAGNOSTIC, \ 299 "Inline arraycopy native that is known to be part of " \ 300 "base library DLL") \ 301 \ 302 product(bool, InlineObjectHash, true, DIAGNOSTIC, \ 303 "Inline Object::hashCode() native that is known to be part " \ 304 "of base library DLL") \ 305 \ 306 product(bool, InlineNatives, true, DIAGNOSTIC, \ 307 "Inline natives that are known to be part of base library DLL") \ 308 \ 309 product(bool, InlineMathNatives, true, DIAGNOSTIC, \ 310 "Inline SinD, CosD, etc.") \ 311 \ 312 product(bool, InlineClassNatives, true, DIAGNOSTIC, \ 313 "Inline Class.isInstance, etc") \ 314 \ 315 product(bool, InlineThreadNatives, true, DIAGNOSTIC, \ 316 "Inline Thread.currentThread, etc") \ 317 \ 318 product(bool, InlineUnsafeOps, true, DIAGNOSTIC, \ 319 "Inline memory ops (native methods) from Unsafe") \ 320 \ 321 product(bool, CriticalJNINatives, false, \ 322 "(Deprecated) Check for critical JNI entry points") \ 323 \ 324 product(bool, UseAESIntrinsics, false, DIAGNOSTIC, \ 325 "Use intrinsics for AES versions of crypto") \ 326 \ 327 product(bool, UseAESCTRIntrinsics, false, DIAGNOSTIC, \ 328 "Use intrinsics for the paralleled version of AES/CTR crypto") \ 329 \ 330 product(bool, UseMD5Intrinsics, false, DIAGNOSTIC, \ 331 "Use intrinsics for MD5 crypto hash function") \ 332 \ 333 product(bool, UseSHA1Intrinsics, false, DIAGNOSTIC, \ 334 "Use intrinsics for SHA-1 crypto hash function. " \ 335 "Requires that UseSHA is enabled.") \ 336 \ 337 product(bool, UseSHA256Intrinsics, false, DIAGNOSTIC, \ 338 "Use intrinsics for SHA-224 and SHA-256 crypto hash functions. " \ 339 "Requires that UseSHA is enabled.") \ 340 \ 341 product(bool, UseSHA512Intrinsics, false, DIAGNOSTIC, \ 342 "Use intrinsics for SHA-384 and SHA-512 crypto hash functions. " \ 343 "Requires that UseSHA is enabled.") \ 344 \ 345 product(bool, UseSHA3Intrinsics, false, DIAGNOSTIC, \ 346 "Use intrinsics for SHA3 crypto hash function. " \ 347 "Requires that UseSHA is enabled.") \ 348 \ 349 product(bool, UseCRC32Intrinsics, false, DIAGNOSTIC, \ 350 "use intrinsics for java.util.zip.CRC32") \ 351 \ 352 product(bool, UseCRC32CIntrinsics, false, DIAGNOSTIC, \ 353 "use intrinsics for java.util.zip.CRC32C") \ 354 \ 355 product(bool, UseAdler32Intrinsics, false, DIAGNOSTIC, \ 356 "use intrinsics for java.util.zip.Adler32") \ 357 \ 358 product(bool, UseVectorizedMismatchIntrinsic, false, DIAGNOSTIC, \ 359 "Enables intrinsification of ArraysSupport.vectorizedMismatch()") \ 360 \ 361 product(bool, UseCopySignIntrinsic, false, DIAGNOSTIC, \ 362 "Enables intrinsification of Math.copySign") \ 363 \ 364 product(bool, UseSignumIntrinsic, false, DIAGNOSTIC, \ 365 "Enables intrinsification of Math.signum") \ 366 \ 367 product(ccstrlist, DisableIntrinsic, "", DIAGNOSTIC, \ 368 "do not expand intrinsics whose (internal) names appear here") \ 369 constraint(DisableIntrinsicConstraintFunc,AfterErgo) \ 370 \ 371 product(ccstrlist, ControlIntrinsic, "", DIAGNOSTIC, \ 372 "Control intrinsics using a list of +/- (internal) names, " \ 373 "separated by commas") \ 374 constraint(ControlIntrinsicConstraintFunc,AfterErgo) \ 375 \ 376 develop(bool, TraceCallFixup, false, \ 377 "Trace all call fixups") \ 378 \ 379 develop(bool, DeoptimizeALot, false, \ 380 "Deoptimize at every exit from the runtime system") \ 381 \ 382 notproduct(ccstrlist, DeoptimizeOnlyAt, "", \ 383 "A comma separated list of bcis to deoptimize at") \ 384 \ 385 develop(bool, DeoptimizeRandom, false, \ 386 "Deoptimize random frames on random exit from the runtime system")\ 387 \ 388 notproduct(bool, ZombieALot, false, \ 389 "Create zombies (non-entrant) at exit from the runtime system") \ 390 \ 391 notproduct(bool, WalkStackALot, false, \ 392 "Trace stack (no print) at every exit from the runtime system") \ 393 \ 394 develop(bool, DeoptimizeObjectsALot, false, \ 395 "For testing purposes concurrent threads revert optimizations " \ 396 "based on escape analysis at intervals given with " \ 397 "DeoptimizeObjectsALotInterval=n. The thread count is given " \ 398 "with DeoptimizeObjectsALotThreadCountSingle and " \ 399 "DeoptimizeObjectsALotThreadCountAll.") \ 400 \ 401 develop(uint64_t, DeoptimizeObjectsALotInterval, 5, \ 402 "Interval for DeoptimizeObjectsALot.") \ 403 range(0, max_jlong) \ 404 \ 405 develop(int, DeoptimizeObjectsALotThreadCountSingle, 1, \ 406 "The number of threads that revert optimizations based on " \ 407 "escape analysis for a single thread if DeoptimizeObjectsALot " \ 408 "is enabled. The target thread is selected round robin." ) \ 409 range(0, max_jint) \ 410 \ 411 develop(int, DeoptimizeObjectsALotThreadCountAll, 1, \ 412 "The number of threads that revert optimizations based on " \ 413 "escape analysis for all threads if DeoptimizeObjectsALot " \ 414 "is enabled." ) \ 415 range(0, max_jint) \ 416 \ 417 notproduct(bool, VerifyLastFrame, false, \ 418 "Verify oops on last frame on entry to VM") \ 419 \ 420 product(bool, SafepointTimeout, false, \ 421 "Time out and warn or fail after SafepointTimeoutDelay " \ 422 "milliseconds if failed to reach safepoint") \ 423 \ 424 product(bool, AbortVMOnSafepointTimeout, false, DIAGNOSTIC, \ 425 "Abort upon failure to reach safepoint (see SafepointTimeout)") \ 426 \ 427 product(bool, AbortVMOnVMOperationTimeout, false, DIAGNOSTIC, \ 428 "Abort upon failure to complete VM operation promptly") \ 429 \ 430 product(intx, AbortVMOnVMOperationTimeoutDelay, 1000, DIAGNOSTIC, \ 431 "Delay in milliseconds for option AbortVMOnVMOperationTimeout") \ 432 range(0, max_intx) \ 433 \ 434 product(bool, MaxFDLimit, true, \ 435 "Bump the number of file descriptors to maximum (Unix only)") \ 436 \ 437 product(bool, LogEvents, true, DIAGNOSTIC, \ 438 "Enable the various ring buffer event logs") \ 439 \ 440 product(uintx, LogEventsBufferEntries, 20, DIAGNOSTIC, \ 441 "Number of ring buffer event logs") \ 442 range(1, NOT_LP64(1*K) LP64_ONLY(1*M)) \ 443 \ 444 product(bool, BytecodeVerificationRemote, true, DIAGNOSTIC, \ 445 "Enable the Java bytecode verifier for remote classes") \ 446 \ 447 product(bool, BytecodeVerificationLocal, false, DIAGNOSTIC, \ 448 "Enable the Java bytecode verifier for local classes") \ 449 \ 450 develop(bool, VerifyStackAtCalls, false, \ 451 "Verify that the stack pointer is unchanged after calls") \ 452 \ 453 develop(bool, TraceJavaAssertions, false, \ 454 "Trace java language assertions") \ 455 \ 456 notproduct(bool, VerifyCodeCache, false, \ 457 "Verify code cache on memory allocation/deallocation") \ 458 \ 459 develop(bool, UseMallocOnly, false, \ 460 "Use only malloc/free for allocation (no resource area/arena)") \ 461 \ 462 develop(bool, ZapResourceArea, trueInDebug, \ 463 "Zap freed resource/arena space") \ 464 \ 465 notproduct(bool, ZapVMHandleArea, trueInDebug, \ 466 "Zap freed VM handle space") \ 467 \ 468 notproduct(bool, ZapStackSegments, trueInDebug, \ 469 "Zap allocated/freed stack segments") \ 470 \ 471 develop(bool, ZapUnusedHeapArea, trueInDebug, \ 472 "Zap unused heap space") \ 473 \ 474 develop(bool, CheckZapUnusedHeapArea, false, \ 475 "Check zapping of unused heap space") \ 476 \ 477 develop(bool, ZapFillerObjects, trueInDebug, \ 478 "Zap filler objects") \ 479 \ 480 product(bool, ExecutingUnitTests, false, \ 481 "Whether the JVM is running unit tests or not") \ 482 \ 483 develop(uintx, ErrorHandlerTest, 0, \ 484 "If > 0, provokes an error after VM initialization; the value " \ 485 "determines which error to provoke. See controlled_crash() " \ 486 "in vmError.cpp.") \ 487 range(0, 17) \ 488 \ 489 develop(uintx, TestCrashInErrorHandler, 0, \ 490 "If > 0, provokes an error inside VM error handler (a secondary " \ 491 "crash). see controlled_crash() in vmError.cpp") \ 492 range(0, 17) \ 493 \ 494 develop(bool, TestSafeFetchInErrorHandler, false , \ 495 "If true, tests SafeFetch inside error handler.") \ 496 \ 497 develop(bool, TestUnresponsiveErrorHandler, false, \ 498 "If true, simulates an unresponsive error handler.") \ 499 \ 500 develop(bool, Verbose, false, \ 501 "Print additional debugging information from other modes") \ 502 \ 503 develop(bool, PrintMiscellaneous, false, \ 504 "Print uncategorized debugging information (requires +Verbose)") \ 505 \ 506 develop(bool, WizardMode, false, \ 507 "Print much more debugging information") \ 508 \ 509 product(bool, ShowMessageBoxOnError, false, \ 510 "Keep process alive on VM fatal error") \ 511 \ 512 product(bool, CreateCoredumpOnCrash, true, \ 513 "Create core/mini dump on VM fatal error") \ 514 \ 515 product(uint64_t, ErrorLogTimeout, 2 * 60, \ 516 "Timeout, in seconds, to limit the time spent on writing an " \ 517 "error log in case of a crash.") \ 518 range(0, (uint64_t)max_jlong/1000) \ 519 \ 520 product(bool, SuppressFatalErrorMessage, false, \ 521 "Report NO fatal error message (avoid deadlock)") \ 522 \ 523 product(ccstrlist, OnError, "", \ 524 "Run user-defined commands on fatal error; see VMError.cpp " \ 525 "for examples") \ 526 \ 527 product(ccstrlist, OnOutOfMemoryError, "", \ 528 "Run user-defined commands on first java.lang.OutOfMemoryError " \ 529 "thrown from JVM") \ 530 \ 531 product(bool, HeapDumpBeforeFullGC, false, MANAGEABLE, \ 532 "Dump heap to file before any major stop-the-world GC") \ 533 \ 534 product(bool, HeapDumpAfterFullGC, false, MANAGEABLE, \ 535 "Dump heap to file after any major stop-the-world GC") \ 536 \ 537 product(bool, HeapDumpOnOutOfMemoryError, false, MANAGEABLE, \ 538 "Dump heap to file when java.lang.OutOfMemoryError is thrown " \ 539 "from JVM") \ 540 \ 541 product(ccstr, HeapDumpPath, NULL, MANAGEABLE, \ 542 "When HeapDumpOnOutOfMemoryError is on, the path (filename or " \ 543 "directory) of the dump file (defaults to java_pid<pid>.hprof " \ 544 "in the working directory)") \ 545 \ 546 product(intx, HeapDumpGzipLevel, 0, MANAGEABLE, \ 547 "When HeapDumpOnOutOfMemoryError is on, the gzip compression " \ 548 "level of the dump file. 0 (the default) disables gzip " \ 549 "compression. Otherwise the level must be between 1 and 9.") \ 550 range(0, 9) \ 551 \ 552 product(ccstr, NativeMemoryTracking, DEBUG_ONLY("summary") NOT_DEBUG("off"), \ 553 "Native memory tracking options") \ 554 \ 555 product(bool, PrintNMTStatistics, false, DIAGNOSTIC, \ 556 "Print native memory tracking summary data if it is on") \ 557 \ 558 product(bool, LogCompilation, false, DIAGNOSTIC, \ 559 "Log compilation activity in detail to LogFile") \ 560 \ 561 product(bool, PrintCompilation, false, \ 562 "Print compilations") \ 563 \ 564 product(intx, RepeatCompilation, 0, DIAGNOSTIC, \ 565 "Repeat compilation without installing code (number of times)") \ 566 range(0, max_jint) \ 567 \ 568 product(bool, PrintExtendedThreadInfo, false, \ 569 "Print more information in thread dump") \ 570 \ 571 product(intx, ScavengeRootsInCode, 2, DIAGNOSTIC, \ 572 "0: do not allow scavengable oops in the code cache; " \ 573 "1: allow scavenging from the code cache; " \ 574 "2: emit as many constants as the compiler can see") \ 575 range(0, 2) \ 576 \ 577 product(bool, AlwaysRestoreFPU, false, \ 578 "Restore the FPU control word after every JNI call (expensive)") \ 579 \ 580 product(bool, PrintCompilation2, false, DIAGNOSTIC, \ 581 "Print additional statistics per compilation") \ 582 \ 583 product(bool, PrintAdapterHandlers, false, DIAGNOSTIC, \ 584 "Print code generated for i2c/c2i adapters") \ 585 \ 586 product(bool, VerifyAdapterCalls, trueInDebug, DIAGNOSTIC, \ 587 "Verify that i2c/c2i adapters are called properly") \ 588 \ 589 develop(bool, VerifyAdapterSharing, false, \ 590 "Verify that the code for shared adapters is the equivalent") \ 591 \ 592 product(bool, PrintAssembly, false, DIAGNOSTIC, \ 593 "Print assembly code (using external disassembler.so)") \ 594 \ 595 product(ccstr, PrintAssemblyOptions, NULL, DIAGNOSTIC, \ 596 "Print options string passed to disassembler.so") \ 597 \ 598 notproduct(bool, PrintNMethodStatistics, false, \ 599 "Print a summary statistic for the generated nmethods") \ 600 \ 601 product(bool, PrintNMethods, false, DIAGNOSTIC, \ 602 "Print assembly code for nmethods when generated") \ 603 \ 604 product(bool, PrintNativeNMethods, false, DIAGNOSTIC, \ 605 "Print assembly code for native nmethods when generated") \ 606 \ 607 develop(bool, PrintDebugInfo, false, \ 608 "Print debug information for all nmethods when generated") \ 609 \ 610 develop(bool, PrintRelocations, false, \ 611 "Print relocation information for all nmethods when generated") \ 612 \ 613 develop(bool, PrintDependencies, false, \ 614 "Print dependency information for all nmethods when generated") \ 615 \ 616 develop(bool, PrintExceptionHandlers, false, \ 617 "Print exception handler tables for all nmethods when generated") \ 618 \ 619 develop(bool, StressCompiledExceptionHandlers, false, \ 620 "Exercise compiled exception handlers") \ 621 \ 622 develop(bool, InterceptOSException, false, \ 623 "Start debugger when an implicit OS (e.g. NULL) " \ 624 "exception happens") \ 625 \ 626 product(bool, PrintCodeCache, false, \ 627 "Print the code cache memory usage when exiting") \ 628 \ 629 develop(bool, PrintCodeCache2, false, \ 630 "Print detailed usage information on the code cache when exiting")\ 631 \ 632 product(bool, PrintCodeCacheOnCompilation, false, \ 633 "Print the code cache memory usage each time a method is " \ 634 "compiled") \ 635 \ 636 product(bool, PrintCodeHeapAnalytics, false, DIAGNOSTIC, \ 637 "Print code heap usage statistics on exit and on full condition") \ 638 \ 639 product(bool, PrintStubCode, false, DIAGNOSTIC, \ 640 "Print generated stub code") \ 641 \ 642 product(bool, StackTraceInThrowable, true, \ 643 "Collect backtrace in throwable when exception happens") \ 644 \ 645 product(bool, OmitStackTraceInFastThrow, true, \ 646 "Omit backtraces for some 'hot' exceptions in optimized code") \ 647 \ 648 product(bool, ShowCodeDetailsInExceptionMessages, true, MANAGEABLE, \ 649 "Show exception messages from RuntimeExceptions that contain " \ 650 "snippets of the failing code. Disable this to improve privacy.") \ 651 \ 652 product(bool, PrintWarnings, true, \ 653 "Print JVM warnings to output stream") \ 654 \ 655 product(bool, RegisterFinalizersAtInit, true, \ 656 "Register finalizable objects at end of Object.<init> or " \ 657 "after allocation") \ 658 \ 659 develop(bool, RegisterReferences, true, \ 660 "Tell whether the VM should register soft/weak/final/phantom " \ 661 "references") \ 662 \ 663 develop(bool, PrintCodeCacheExtension, false, \ 664 "Print extension of code cache") \ 665 \ 666 develop(bool, UsePrivilegedStack, true, \ 667 "Enable the security JVM functions") \ 668 \ 669 product(bool, ClassUnloading, true, \ 670 "Do unloading of classes") \ 671 \ 672 product(bool, ClassUnloadingWithConcurrentMark, true, \ 673 "Do unloading of classes with a concurrent marking cycle") \ 674 \ 675 notproduct(bool, PrintSystemDictionaryAtExit, false, \ 676 "Print the system dictionary at exit") \ 677 \ 678 notproduct(bool, PrintClassLoaderDataGraphAtExit, false, \ 679 "Print the class loader data graph at exit") \ 680 \ 681 product(bool, DynamicallyResizeSystemDictionaries, true, DIAGNOSTIC, \ 682 "Dynamically resize system dictionaries as needed") \ 683 \ 684 product(bool, AlwaysLockClassLoader, false, \ 685 "(Deprecated) Require the VM to acquire the class loader lock " \ 686 "before calling loadClass() even for class loaders registering " \ 687 "as parallel capable") \ 688 \ 689 product(bool, AllowParallelDefineClass, false, \ 690 "Allow parallel defineClass requests for class loaders " \ 691 "registering as parallel capable") \ 692 \ 693 product_pd(bool, DontYieldALot, \ 694 "Throw away obvious excess yield calls") \ 695 \ 696 product(bool, DisablePrimordialThreadGuardPages, false, EXPERIMENTAL, \ 697 "Disable the use of stack guard pages if the JVM is loaded " \ 698 "on the primordial process thread") \ 699 \ 700 /* notice: the max range value here is max_jint, not max_intx */ \ 701 /* because of overflow issue */ \ 702 product(intx, AsyncDeflationInterval, 250, DIAGNOSTIC, \ 703 "Async deflate idle monitors every so many milliseconds when " \ 704 "MonitorUsedDeflationThreshold is exceeded (0 is off).") \ 705 range(0, max_jint) \ 706 \ 707 /* notice: the max range value here is max_jint, not max_intx */ \ 708 /* because of overflow issue */ \ 709 product(intx, GuaranteedAsyncDeflationInterval, 60000, DIAGNOSTIC, \ 710 "Async deflate idle monitors every so many milliseconds even " \ 711 "when MonitorUsedDeflationThreshold is NOT exceeded (0 is off).") \ 712 range(0, max_jint) \ 713 \ 714 product(size_t, AvgMonitorsPerThreadEstimate, 1024, DIAGNOSTIC, \ 715 "Used to estimate a variable ceiling based on number of threads " \ 716 "for use with MonitorUsedDeflationThreshold (0 is off).") \ 717 range(0, max_uintx) \ 718 \ 719 /* notice: the max range value here is max_jint, not max_intx */ \ 720 /* because of overflow issue */ \ 721 product(intx, MonitorDeflationMax, 1000000, DIAGNOSTIC, \ 722 "The maximum number of monitors to deflate, unlink and delete " \ 723 "at one time (minimum is 1024).") \ 724 range(1024, max_jint) \ 725 \ 726 product(intx, MonitorUsedDeflationThreshold, 90, DIAGNOSTIC, \ 727 "Percentage of used monitors before triggering deflation (0 is " \ 728 "off). The check is performed on GuaranteedSafepointInterval, " \ 729 "AsyncDeflationInterval or GuaranteedAsyncDeflationInterval, " \ 730 "whichever is lower.") \ 731 range(0, 100) \ 732 \ 733 product(uintx, NoAsyncDeflationProgressMax, 3, DIAGNOSTIC, \ 734 "Max number of no progress async deflation attempts to tolerate " \ 735 "before adjusting the in_use_list_ceiling up (0 is off).") \ 736 range(0, max_uintx) \ 737 \ 738 product(intx, hashCode, 5, EXPERIMENTAL, \ 739 "(Unstable) select hashCode generation algorithm") \ 740 \ 741 product(bool, FilterSpuriousWakeups, true, \ 742 "When true prevents OS-level spurious, or premature, wakeups " \ 743 "from Object.wait (Ignored for Windows)") \ 744 \ 745 product(bool, ReduceSignalUsage, false, \ 746 "Reduce the use of OS signals in Java and/or the VM") \ 747 \ 748 develop(bool, LoadLineNumberTables, true, \ 749 "Tell whether the class file parser loads line number tables") \ 750 \ 751 develop(bool, LoadLocalVariableTables, true, \ 752 "Tell whether the class file parser loads local variable tables") \ 753 \ 754 develop(bool, LoadLocalVariableTypeTables, true, \ 755 "Tell whether the class file parser loads local variable type" \ 756 "tables") \ 757 \ 758 product(bool, AllowUserSignalHandlers, false, \ 759 "Application will install primary signal handlers for the JVM " \ 760 "(Unix only)") \ 761 \ 762 product(bool, UseSignalChaining, true, \ 763 "Use signal-chaining to invoke signal handlers installed " \ 764 "by the application (Unix only)") \ 765 \ 766 product(bool, RestoreMXCSROnJNICalls, false, \ 767 "Restore MXCSR when returning from JNI calls") \ 768 \ 769 product(bool, CheckJNICalls, false, \ 770 "Verify all arguments to JNI calls") \ 771 \ 772 product(bool, UseFastJNIAccessors, true, \ 773 "Use optimized versions of Get<Primitive>Field") \ 774 \ 775 product(intx, MaxJNILocalCapacity, 65536, \ 776 "Maximum allowable local JNI handle capacity to " \ 777 "EnsureLocalCapacity() and PushLocalFrame(), " \ 778 "where <= 0 is unlimited, default: 65536") \ 779 range(min_intx, max_intx) \ 780 \ 781 product(bool, EagerXrunInit, false, \ 782 "Eagerly initialize -Xrun libraries; allows startup profiling, " \ 783 "but not all -Xrun libraries may support the state of the VM " \ 784 "at this time") \ 785 \ 786 product(bool, PreserveAllAnnotations, false, \ 787 "Preserve RuntimeInvisibleAnnotations as well " \ 788 "as RuntimeVisibleAnnotations") \ 789 \ 790 develop(uintx, PreallocatedOutOfMemoryErrorCount, 4, \ 791 "Number of OutOfMemoryErrors preallocated with backtrace") \ 792 \ 793 product(bool, UseXMMForArrayCopy, false, \ 794 "Use SSE2 MOVQ instruction for Arraycopy") \ 795 \ 796 notproduct(bool, PrintFieldLayout, false, \ 797 "Print field layout for each class") \ 798 \ 799 /* Need to limit the extent of the padding to reasonable size. */\ 800 /* 8K is well beyond the reasonable HW cache line size, even with */\ 801 /* aggressive prefetching, while still leaving the room for segregating */\ 802 /* among the distinct pages. */\ 803 product(intx, ContendedPaddingWidth, 128, \ 804 "How many bytes to pad the fields/classes marked @Contended with")\ 805 range(0, 8192) \ 806 constraint(ContendedPaddingWidthConstraintFunc,AfterErgo) \ 807 \ 808 product(bool, EnableContended, true, \ 809 "Enable @Contended annotation support") \ 810 \ 811 product(bool, RestrictContended, true, \ 812 "Restrict @Contended to trusted classes") \ 813 \ 814 product(bool, UseBiasedLocking, false, \ 815 "(Deprecated) Enable biased locking in JVM") \ 816 \ 817 product(intx, BiasedLockingStartupDelay, 0, \ 818 "(Deprecated) Number of milliseconds to wait before enabling " \ 819 "biased locking") \ 820 range(0, (intx)(max_jint-(max_jint%PeriodicTask::interval_gran))) \ 821 constraint(BiasedLockingStartupDelayFunc,AfterErgo) \ 822 \ 823 product(bool, PrintBiasedLockingStatistics, false, DIAGNOSTIC, \ 824 "(Deprecated) Print statistics of biased locking in JVM") \ 825 \ 826 product(intx, BiasedLockingBulkRebiasThreshold, 20, \ 827 "(Deprecated) Threshold of number of revocations per type to " \ 828 "try to rebias all objects in the heap of that type") \ 829 range(0, max_intx) \ 830 constraint(BiasedLockingBulkRebiasThresholdFunc,AfterErgo) \ 831 \ 832 product(intx, BiasedLockingBulkRevokeThreshold, 40, \ 833 "(Deprecated) Threshold of number of revocations per type to " \ 834 "permanently revoke biases of all objects in the heap of that " \ 835 "type") \ 836 range(0, max_intx) \ 837 constraint(BiasedLockingBulkRevokeThresholdFunc,AfterErgo) \ 838 \ 839 product(intx, BiasedLockingDecayTime, 25000, \ 840 "(Deprecated) Decay time (in milliseconds) to re-enable bulk " \ 841 "rebiasing of a type after previous bulk rebias") \ 842 range(500, max_intx) \ 843 constraint(BiasedLockingDecayTimeFunc,AfterErgo) \ 844 \ 845 product(intx, DiagnoseSyncOnValueBasedClasses, 0, DIAGNOSTIC, \ 846 "Detect and take action upon identifying synchronization on " \ 847 "value based classes. Modes: " \ 848 "0: off; " \ 849 "1: exit with fatal error; " \ 850 "2: log message to stdout. Output file can be specified with " \ 851 " -Xlog:valuebasedclasses. If JFR is running it will " \ 852 " also generate JFR events.") \ 853 range(0, 2) \ 854 \ 855 product(bool, ExitOnOutOfMemoryError, false, \ 856 "JVM exits on the first occurrence of an out-of-memory error " \ 857 "thrown from JVM") \ 858 \ 859 product(bool, CrashOnOutOfMemoryError, false, \ 860 "JVM aborts, producing an error log and core/mini dump, on the " \ 861 "first occurrence of an out-of-memory error thrown from JVM") \ 862 \ 863 /* tracing */ \ 864 \ 865 develop(bool, StressRewriter, false, \ 866 "Stress linktime bytecode rewriting") \ 867 \ 868 product(ccstr, TraceJVMTI, NULL, \ 869 "Trace flags for JVMTI functions and events") \ 870 \ 871 product(bool, StressLdcRewrite, false, DIAGNOSTIC, \ 872 "Force ldc -> ldc_w rewrite during RedefineClasses. " \ 873 "This option can change an EMCP method into an obsolete method " \ 874 "and can affect tests that expect specific methods to be EMCP. " \ 875 "This option should be used with caution.") \ 876 \ 877 product(bool, AllowRedefinitionToAddDeleteMethods, false, \ 878 "(Deprecated) Allow redefinition to add and delete private " \ 879 "static or final methods for compatibility with old releases") \ 880 \ 881 develop(bool, TraceBytecodes, false, \ 882 "Trace bytecode execution") \ 883 \ 884 develop(bool, TraceICs, false, \ 885 "Trace inline cache changes") \ 886 \ 887 notproduct(bool, TraceInvocationCounterOverflow, false, \ 888 "Trace method invocation counter overflow") \ 889 \ 890 develop(bool, TraceInlineCacheClearing, false, \ 891 "Trace clearing of inline caches in nmethods") \ 892 \ 893 develop(bool, TraceDependencies, false, \ 894 "Trace dependencies") \ 895 \ 896 develop(bool, VerifyDependencies, trueInDebug, \ 897 "Exercise and verify the compilation dependency mechanism") \ 898 \ 899 develop(bool, TraceNewOopMapGeneration, false, \ 900 "Trace OopMapGeneration") \ 901 \ 902 develop(bool, TraceNewOopMapGenerationDetailed, false, \ 903 "Trace OopMapGeneration: print detailed cell states") \ 904 \ 905 develop(bool, TimeOopMap, false, \ 906 "Time calls to GenerateOopMap::compute_map() in sum") \ 907 \ 908 develop(bool, TimeOopMap2, false, \ 909 "Time calls to GenerateOopMap::compute_map() individually") \ 910 \ 911 develop(bool, TraceOopMapRewrites, false, \ 912 "Trace rewriting of methods during oop map generation") \ 913 \ 914 develop(bool, TraceICBuffer, false, \ 915 "Trace usage of IC buffer") \ 916 \ 917 develop(bool, TraceCompiledIC, false, \ 918 "Trace changes of compiled IC") \ 919 \ 920 develop(bool, FLSVerifyDictionary, false, \ 921 "Do lots of (expensive) FLS dictionary verification") \ 922 \ 923 \ 924 notproduct(bool, CheckMemoryInitialization, false, \ 925 "Check memory initialization") \ 926 \ 927 product(uintx, ProcessDistributionStride, 4, \ 928 "Stride through processors when distributing processes") \ 929 range(0, max_juint) \ 930 \ 931 develop(bool, TraceFinalizerRegistration, false, \ 932 "Trace registration of final references") \ 933 \ 934 product(bool, IgnoreEmptyClassPaths, false, \ 935 "Ignore empty path elements in -classpath") \ 936 \ 937 product(bool, PrintHeapAtSIGBREAK, true, \ 938 "Print heap layout in response to SIGBREAK") \ 939 \ 940 product(bool, PrintClassHistogram, false, MANAGEABLE, \ 941 "Print a histogram of class instances") \ 942 \ 943 product(double, ObjectCountCutOffPercent, 0.5, EXPERIMENTAL, \ 944 "The percentage of the used heap that the instances of a class " \ 945 "must occupy for the class to generate a trace event") \ 946 range(0.0, 100.0) \ 947 \ 948 /* JVMTI heap profiling */ \ 949 \ 950 product(bool, VerifyBeforeIteration, false, DIAGNOSTIC, \ 951 "Verify memory system before JVMTI iteration") \ 952 \ 953 /* compiler */ \ 954 \ 955 /* notice: the max range value here is max_jint, not max_intx */ \ 956 /* because of overflow issue */ \ 957 product(intx, CICompilerCount, CI_COMPILER_COUNT, \ 958 "Number of compiler threads to run") \ 959 range(0, max_jint) \ 960 constraint(CICompilerCountConstraintFunc, AfterErgo) \ 961 \ 962 product(bool, UseDynamicNumberOfCompilerThreads, true, \ 963 "Dynamically choose the number of parallel compiler threads") \ 964 \ 965 product(bool, ReduceNumberOfCompilerThreads, true, DIAGNOSTIC, \ 966 "Reduce the number of parallel compiler threads when they " \ 967 "are not used") \ 968 \ 969 product(bool, TraceCompilerThreads, false, DIAGNOSTIC, \ 970 "Trace creation and removal of compiler threads") \ 971 \ 972 develop(bool, InjectCompilerCreationFailure, false, \ 973 "Inject thread creation failures for " \ 974 "UseDynamicNumberOfCompilerThreads") \ 975 \ 976 develop(bool, GenerateSynchronizationCode, true, \ 977 "generate locking/unlocking code for synchronized methods and " \ 978 "monitors") \ 979 \ 980 develop(bool, GenerateRangeChecks, true, \ 981 "Generate range checks for array accesses") \ 982 \ 983 product_pd(bool, ImplicitNullChecks, DIAGNOSTIC, \ 984 "Generate code for implicit null checks") \ 985 \ 986 product_pd(bool, TrapBasedNullChecks, \ 987 "Generate code for null checks that uses a cmp and trap " \ 988 "instruction raising SIGTRAP. This is only used if an access to" \ 989 "null (+offset) will not raise a SIGSEGV, i.e.," \ 990 "ImplicitNullChecks don't work (PPC64).") \ 991 \ 992 product(bool, EnableThreadSMRExtraValidityChecks, true, DIAGNOSTIC, \ 993 "Enable Thread SMR extra validity checks") \ 994 \ 995 product(bool, EnableThreadSMRStatistics, trueInDebug, DIAGNOSTIC, \ 996 "Enable Thread SMR Statistics") \ 997 \ 998 product(bool, UseNotificationThread, true, \ 999 "Use Notification Thread") \ 1000 \ 1001 product(bool, Inline, true, \ 1002 "Enable inlining") \ 1003 \ 1004 product(bool, ClipInlining, true, \ 1005 "Clip inlining if aggregate method exceeds DesiredMethodLimit") \ 1006 \ 1007 develop(bool, UseCHA, true, \ 1008 "Enable CHA") \ 1009 \ 1010 product(bool, UseVtableBasedCHA, true, DIAGNOSTIC, \ 1011 "Use vtable information during CHA") \ 1012 \ 1013 product(bool, UseTypeProfile, true, \ 1014 "Check interpreter profile for historically monomorphic calls") \ 1015 \ 1016 product(bool, PrintInlining, false, DIAGNOSTIC, \ 1017 "Print inlining optimizations") \ 1018 \ 1019 product(bool, UsePopCountInstruction, false, \ 1020 "Use population count instruction") \ 1021 \ 1022 develop(bool, EagerInitialization, false, \ 1023 "Eagerly initialize classes if possible") \ 1024 \ 1025 product(bool, LogTouchedMethods, false, DIAGNOSTIC, \ 1026 "Log methods which have been ever touched in runtime") \ 1027 \ 1028 product(bool, PrintTouchedMethodsAtExit, false, DIAGNOSTIC, \ 1029 "Print all methods that have been ever touched in runtime") \ 1030 \ 1031 develop(bool, TraceMethodReplacement, false, \ 1032 "Print when methods are replaced do to recompilation") \ 1033 \ 1034 develop(bool, PrintMethodFlushing, false, \ 1035 "Print the nmethods being flushed") \ 1036 \ 1037 product(bool, PrintMethodFlushingStatistics, false, DIAGNOSTIC, \ 1038 "print statistics about method flushing") \ 1039 \ 1040 product(intx, HotMethodDetectionLimit, 100000, DIAGNOSTIC, \ 1041 "Number of compiled code invocations after which " \ 1042 "the method is considered as hot by the flusher") \ 1043 range(1, max_jint) \ 1044 \ 1045 product(intx, MinPassesBeforeFlush, 10, DIAGNOSTIC, \ 1046 "Minimum number of sweeper passes before an nmethod " \ 1047 "can be flushed") \ 1048 range(0, max_intx) \ 1049 \ 1050 product(bool, UseCodeAging, true, \ 1051 "Insert counter to detect warm methods") \ 1052 \ 1053 product(bool, StressCodeAging, false, DIAGNOSTIC, \ 1054 "Start with counters compiled in") \ 1055 \ 1056 develop(bool, StressCodeBuffers, false, \ 1057 "Exercise code buffer expansion and other rare state changes") \ 1058 \ 1059 product(bool, DebugNonSafepoints, trueInDebug, DIAGNOSTIC, \ 1060 "Generate extra debugging information for non-safepoints in " \ 1061 "nmethods") \ 1062 \ 1063 product(bool, PrintVMOptions, false, \ 1064 "Print flags that appeared on the command line") \ 1065 \ 1066 product(bool, IgnoreUnrecognizedVMOptions, false, \ 1067 "Ignore unrecognized VM options") \ 1068 \ 1069 product(bool, PrintCommandLineFlags, false, \ 1070 "Print flags specified on command line or set by ergonomics") \ 1071 \ 1072 product(bool, PrintFlagsInitial, false, \ 1073 "Print all VM flags before argument processing and exit VM") \ 1074 \ 1075 product(bool, PrintFlagsFinal, false, \ 1076 "Print all VM flags after argument and ergonomic processing") \ 1077 \ 1078 notproduct(bool, PrintFlagsWithComments, false, \ 1079 "Print all VM flags with default values and descriptions and " \ 1080 "exit") \ 1081 \ 1082 product(bool, PrintFlagsRanges, false, \ 1083 "Print VM flags and their ranges") \ 1084 \ 1085 product(bool, SerializeVMOutput, true, DIAGNOSTIC, \ 1086 "Use a mutex to serialize output to tty and LogFile") \ 1087 \ 1088 product(bool, DisplayVMOutput, true, DIAGNOSTIC, \ 1089 "Display all VM output on the tty, independently of LogVMOutput") \ 1090 \ 1091 product(bool, LogVMOutput, false, DIAGNOSTIC, \ 1092 "Save VM output to LogFile") \ 1093 \ 1094 product(ccstr, LogFile, NULL, DIAGNOSTIC, \ 1095 "If LogVMOutput or LogCompilation is on, save VM output to " \ 1096 "this file [default: ./hotspot_pid%p.log] (%p replaced with pid)")\ 1097 \ 1098 product(ccstr, ErrorFile, NULL, \ 1099 "If an error occurs, save the error data to this file " \ 1100 "[default: ./hs_err_pid%p.log] (%p replaced with pid)") \ 1101 \ 1102 product(bool, ExtensiveErrorReports, \ 1103 PRODUCT_ONLY(false) NOT_PRODUCT(true), \ 1104 "Error reports are more extensive.") \ 1105 \ 1106 product(bool, DisplayVMOutputToStderr, false, \ 1107 "If DisplayVMOutput is true, display all VM output to stderr") \ 1108 \ 1109 product(bool, DisplayVMOutputToStdout, false, \ 1110 "If DisplayVMOutput is true, display all VM output to stdout") \ 1111 \ 1112 product(bool, ErrorFileToStderr, false, \ 1113 "If true, error data is printed to stderr instead of a file") \ 1114 \ 1115 product(bool, ErrorFileToStdout, false, \ 1116 "If true, error data is printed to stdout instead of a file") \ 1117 \ 1118 product(bool, UseHeavyMonitors, false, \ 1119 "use heavyweight instead of lightweight Java monitors") \ 1120 \ 1121 product(bool, PrintStringTableStatistics, false, \ 1122 "print statistics about the StringTable and SymbolTable") \ 1123 \ 1124 product(bool, VerifyStringTableAtExit, false, DIAGNOSTIC, \ 1125 "verify StringTable contents at exit") \ 1126 \ 1127 notproduct(bool, PrintSymbolTableSizeHistogram, false, \ 1128 "print histogram of the symbol table") \ 1129 \ 1130 product(ccstr, AbortVMOnException, NULL, DIAGNOSTIC, \ 1131 "Call fatal if this exception is thrown. Example: " \ 1132 "java -XX:AbortVMOnException=java.lang.NullPointerException Foo") \ 1133 \ 1134 product(ccstr, AbortVMOnExceptionMessage, NULL, DIAGNOSTIC, \ 1135 "Call fatal if the exception pointed by AbortVMOnException " \ 1136 "has this message") \ 1137 \ 1138 develop(bool, DebugVtables, false, \ 1139 "add debugging code to vtable dispatch") \ 1140 \ 1141 notproduct(bool, PrintVtableStats, false, \ 1142 "print vtables stats at end of run") \ 1143 \ 1144 develop(bool, TraceCreateZombies, false, \ 1145 "trace creation of zombie nmethods") \ 1146 \ 1147 product(bool, RangeCheckElimination, true, \ 1148 "Eliminate range checks") \ 1149 \ 1150 develop_pd(bool, UncommonNullCast, \ 1151 "track occurrences of null in casts; adjust compiler tactics") \ 1152 \ 1153 develop(bool, TypeProfileCasts, true, \ 1154 "treat casts like calls for purposes of type profiling") \ 1155 \ 1156 develop(bool, TraceLivenessGen, false, \ 1157 "Trace the generation of liveness analysis information") \ 1158 \ 1159 notproduct(bool, TraceLivenessQuery, false, \ 1160 "Trace queries of liveness analysis information") \ 1161 \ 1162 notproduct(bool, CollectIndexSetStatistics, false, \ 1163 "Collect information about IndexSets") \ 1164 \ 1165 develop(intx, FastAllocateSizeLimit, 128*K, \ 1166 /* Note: This value is zero mod 1<<13 for a cheap sparc set. */ \ 1167 "Inline allocations larger than this in doublewords must go slow")\ 1168 \ 1169 product_pd(bool, CompactStrings, \ 1170 "Enable Strings to use single byte chars in backing store") \ 1171 \ 1172 product_pd(uintx, TypeProfileLevel, \ 1173 "=XYZ, with Z: Type profiling of arguments at call; " \ 1174 "Y: Type profiling of return value at call; " \ 1175 "X: Type profiling of parameters to methods; " \ 1176 "X, Y and Z in 0=off ; 1=jsr292 only; 2=all methods") \ 1177 constraint(TypeProfileLevelConstraintFunc, AfterErgo) \ 1178 \ 1179 product(intx, TypeProfileArgsLimit, 2, \ 1180 "max number of call arguments to consider for type profiling") \ 1181 range(0, 16) \ 1182 \ 1183 product(intx, TypeProfileParmsLimit, 2, \ 1184 "max number of incoming parameters to consider for type profiling"\ 1185 ", -1 for all") \ 1186 range(-1, 64) \ 1187 \ 1188 /* statistics */ \ 1189 develop(bool, CountCompiledCalls, false, \ 1190 "Count method invocations") \ 1191 \ 1192 notproduct(bool, ICMissHistogram, false, \ 1193 "Produce histogram of IC misses") \ 1194 \ 1195 /* interpreter */ \ 1196 product_pd(bool, RewriteBytecodes, \ 1197 "Allow rewriting of bytecodes (bytecodes are not immutable)") \ 1198 \ 1199 product_pd(bool, RewriteFrequentPairs, \ 1200 "Rewrite frequently used bytecode pairs into a single bytecode") \ 1201 \ 1202 product(bool, PrintInterpreter, false, DIAGNOSTIC, \ 1203 "Print the generated interpreter code") \ 1204 \ 1205 product(bool, UseInterpreter, true, \ 1206 "Use interpreter for non-compiled methods") \ 1207 \ 1208 develop(bool, UseFastSignatureHandlers, true, \ 1209 "Use fast signature handlers for native calls") \ 1210 \ 1211 product(bool, UseLoopCounter, true, \ 1212 "Increment invocation counter on backward branch") \ 1213 \ 1214 product_pd(bool, UseOnStackReplacement, \ 1215 "Use on stack replacement, calls runtime if invoc. counter " \ 1216 "overflows in loop") \ 1217 \ 1218 notproduct(bool, TraceOnStackReplacement, false, \ 1219 "Trace on stack replacement") \ 1220 \ 1221 product_pd(bool, PreferInterpreterNativeStubs, \ 1222 "Use always interpreter stubs for native methods invoked via " \ 1223 "interpreter") \ 1224 \ 1225 develop(bool, CountBytecodes, false, \ 1226 "Count number of bytecodes executed") \ 1227 \ 1228 develop(bool, PrintBytecodeHistogram, false, \ 1229 "Print histogram of the executed bytecodes") \ 1230 \ 1231 develop(bool, PrintBytecodePairHistogram, false, \ 1232 "Print histogram of the executed bytecode pairs") \ 1233 \ 1234 product(bool, PrintSignatureHandlers, false, DIAGNOSTIC, \ 1235 "Print code generated for native method signature handlers") \ 1236 \ 1237 develop(bool, VerifyOops, false, \ 1238 "Do plausibility checks for oops") \ 1239 \ 1240 develop(bool, CheckUnhandledOops, false, \ 1241 "Check for unhandled oops in VM code") \ 1242 \ 1243 develop(bool, VerifyJNIFields, trueInDebug, \ 1244 "Verify jfieldIDs for instance fields") \ 1245 \ 1246 notproduct(bool, VerifyJNIEnvThread, false, \ 1247 "Verify JNIEnv.thread == Thread::current() when entering VM " \ 1248 "from JNI") \ 1249 \ 1250 develop(bool, VerifyFPU, false, \ 1251 "Verify FPU state (check for NaN's, etc.)") \ 1252 \ 1253 develop(bool, VerifyThread, false, \ 1254 "Watch the thread register for corruption (SPARC only)") \ 1255 \ 1256 develop(bool, VerifyActivationFrameSize, false, \ 1257 "Verify that activation frame didn't become smaller than its " \ 1258 "minimal size") \ 1259 \ 1260 develop(bool, TraceFrequencyInlining, false, \ 1261 "Trace frequency based inlining") \ 1262 \ 1263 develop_pd(bool, InlineIntrinsics, \ 1264 "Inline intrinsics that can be statically resolved") \ 1265 \ 1266 product_pd(bool, ProfileInterpreter, \ 1267 "Profile at the bytecode level during interpretation") \ 1268 \ 1269 develop_pd(bool, ProfileTraps, \ 1270 "Profile deoptimization traps at the bytecode level") \ 1271 \ 1272 product(intx, ProfileMaturityPercentage, 20, \ 1273 "number of method invocations/branches (expressed as % of " \ 1274 "CompileThreshold) before using the method's profile") \ 1275 range(0, 100) \ 1276 \ 1277 product(bool, PrintMethodData, false, DIAGNOSTIC, \ 1278 "Print the results of +ProfileInterpreter at end of run") \ 1279 \ 1280 develop(bool, VerifyDataPointer, trueInDebug, \ 1281 "Verify the method data pointer during interpreter profiling") \ 1282 \ 1283 notproduct(bool, CrashGCForDumpingJavaThread, false, \ 1284 "Manually make GC thread crash then dump java stack trace; " \ 1285 "Test only") \ 1286 \ 1287 /* compilation */ \ 1288 product(bool, UseCompiler, true, \ 1289 "Use Just-In-Time compilation") \ 1290 \ 1291 product(bool, UseCounterDecay, true, \ 1292 "Adjust recompilation counters") \ 1293 \ 1294 develop(intx, CounterHalfLifeTime, 30, \ 1295 "Half-life time of invocation counters (in seconds)") \ 1296 \ 1297 develop(intx, CounterDecayMinIntervalLength, 500, \ 1298 "The minimum interval (in milliseconds) between invocation of " \ 1299 "CounterDecay") \ 1300 \ 1301 product(bool, AlwaysCompileLoopMethods, false, \ 1302 "When using recompilation, never interpret methods " \ 1303 "containing loops") \ 1304 \ 1305 product(intx, AllocatePrefetchStyle, 1, \ 1306 "0 = no prefetch, " \ 1307 "1 = generate prefetch instructions for each allocation, " \ 1308 "2 = use TLAB watermark to gate allocation prefetch, " \ 1309 "3 = generate one prefetch instruction per cache line") \ 1310 range(0, 3) \ 1311 \ 1312 product(intx, AllocatePrefetchDistance, -1, \ 1313 "Distance to prefetch ahead of allocation pointer. " \ 1314 "-1: use system-specific value (automatically determined") \ 1315 constraint(AllocatePrefetchDistanceConstraintFunc,AfterMemoryInit)\ 1316 \ 1317 product(intx, AllocatePrefetchLines, 3, \ 1318 "Number of lines to prefetch ahead of array allocation pointer") \ 1319 range(1, 64) \ 1320 \ 1321 product(intx, AllocateInstancePrefetchLines, 1, \ 1322 "Number of lines to prefetch ahead of instance allocation " \ 1323 "pointer") \ 1324 range(1, 64) \ 1325 \ 1326 product(intx, AllocatePrefetchStepSize, 16, \ 1327 "Step size in bytes of sequential prefetch instructions") \ 1328 range(1, 512) \ 1329 constraint(AllocatePrefetchStepSizeConstraintFunc,AfterMemoryInit)\ 1330 \ 1331 product(intx, AllocatePrefetchInstr, 0, \ 1332 "Select instruction to prefetch ahead of allocation pointer") \ 1333 constraint(AllocatePrefetchInstrConstraintFunc, AfterMemoryInit) \ 1334 \ 1335 /* deoptimization */ \ 1336 develop(bool, TraceDeoptimization, false, \ 1337 "Trace deoptimization") \ 1338 \ 1339 develop(bool, PrintDeoptimizationDetails, false, \ 1340 "Print more information about deoptimization") \ 1341 \ 1342 develop(bool, DebugDeoptimization, false, \ 1343 "Tracing various information while debugging deoptimization") \ 1344 \ 1345 product(intx, SelfDestructTimer, 0, \ 1346 "Will cause VM to terminate after a given time (in minutes) " \ 1347 "(0 means off)") \ 1348 range(0, max_intx) \ 1349 \ 1350 product(intx, MaxJavaStackTraceDepth, 1024, \ 1351 "The maximum number of lines in the stack trace for Java " \ 1352 "exceptions (0 means all)") \ 1353 range(0, max_jint/2) \ 1354 \ 1355 /* notice: the max range value here is max_jint, not max_intx */ \ 1356 /* because of overflow issue */ \ 1357 product(intx, GuaranteedSafepointInterval, 1000, DIAGNOSTIC, \ 1358 "Guarantee a safepoint (at least) every so many milliseconds " \ 1359 "(0 means none)") \ 1360 range(0, max_jint) \ 1361 \ 1362 product(intx, SafepointTimeoutDelay, 10000, \ 1363 "Delay in milliseconds for option SafepointTimeout") \ 1364 range(0, max_intx LP64_ONLY(/MICROUNITS)) \ 1365 \ 1366 product(intx, NmethodSweepActivity, 10, \ 1367 "Removes cold nmethods from code cache if > 0. Higher values " \ 1368 "result in more aggressive sweeping") \ 1369 range(0, 2000) \ 1370 \ 1371 notproduct(bool, LogSweeper, false, \ 1372 "Keep a ring buffer of sweeper activity") \ 1373 \ 1374 notproduct(intx, SweeperLogEntries, 1024, \ 1375 "Number of records in the ring buffer of sweeper activity") \ 1376 \ 1377 develop(intx, MallocCatchPtr, -1, \ 1378 "Hit breakpoint when mallocing/freeing this pointer") \ 1379 \ 1380 notproduct(ccstrlist, SuppressErrorAt, "", \ 1381 "List of assertions (file:line) to muzzle") \ 1382 \ 1383 develop(intx, StackPrintLimit, 100, \ 1384 "number of stack frames to print in VM-level stack dump") \ 1385 \ 1386 notproduct(intx, MaxElementPrintSize, 256, \ 1387 "maximum number of elements to print") \ 1388 \ 1389 notproduct(intx, MaxSubklassPrintSize, 4, \ 1390 "maximum number of subklasses to print when printing klass") \ 1391 \ 1392 develop(intx, MaxForceInlineLevel, 100, \ 1393 "maximum number of nested calls that are forced for inlining " \ 1394 "(using CompileCommand or marked w/ @ForceInline)") \ 1395 range(0, max_jint) \ 1396 \ 1397 product(intx, MinInliningThreshold, 250, \ 1398 "The minimum invocation count a method needs to have to be " \ 1399 "inlined") \ 1400 range(0, max_jint) \ 1401 \ 1402 develop(intx, MethodHistogramCutoff, 100, \ 1403 "The cutoff value for method invocation histogram (+CountCalls)") \ 1404 \ 1405 develop(intx, DontYieldALotInterval, 10, \ 1406 "Interval between which yields will be dropped (milliseconds)") \ 1407 \ 1408 notproduct(intx, DeoptimizeALotInterval, 5, \ 1409 "Number of exits until DeoptimizeALot kicks in") \ 1410 \ 1411 notproduct(intx, ZombieALotInterval, 5, \ 1412 "Number of exits until ZombieALot kicks in") \ 1413 \ 1414 product(uintx, MallocMaxTestWords, 0, DIAGNOSTIC, \ 1415 "If non-zero, maximum number of words that malloc/realloc can " \ 1416 "allocate (for testing only)") \ 1417 range(0, max_uintx) \ 1418 \ 1419 product(intx, TypeProfileWidth, 2, \ 1420 "Number of receiver types to record in call/cast profile") \ 1421 range(0, 8) \ 1422 \ 1423 develop(intx, BciProfileWidth, 2, \ 1424 "Number of return bci's to record in ret profile") \ 1425 \ 1426 product(intx, PerMethodRecompilationCutoff, 400, \ 1427 "After recompiling N times, stay in the interpreter (-1=>'Inf')") \ 1428 range(-1, max_intx) \ 1429 \ 1430 product(intx, PerBytecodeRecompilationCutoff, 200, \ 1431 "Per-BCI limit on repeated recompilation (-1=>'Inf')") \ 1432 range(-1, max_intx) \ 1433 \ 1434 product(intx, PerMethodTrapLimit, 100, \ 1435 "Limit on traps (of one kind) in a method (includes inlines)") \ 1436 range(0, max_jint) \ 1437 \ 1438 product(intx, PerMethodSpecTrapLimit, 5000, EXPERIMENTAL, \ 1439 "Limit on speculative traps (of one kind) in a method " \ 1440 "(includes inlines)") \ 1441 range(0, max_jint) \ 1442 \ 1443 product(intx, PerBytecodeTrapLimit, 4, \ 1444 "Limit on traps (of one kind) at a particular BCI") \ 1445 range(0, max_jint) \ 1446 \ 1447 product(intx, SpecTrapLimitExtraEntries, 3, EXPERIMENTAL, \ 1448 "Extra method data trap entries for speculation") \ 1449 \ 1450 develop(intx, InlineFrequencyRatio, 20, \ 1451 "Ratio of call site execution to caller method invocation") \ 1452 range(0, max_jint) \ 1453 \ 1454 product_pd(intx, InlineFrequencyCount, DIAGNOSTIC, \ 1455 "Count of call site execution necessary to trigger frequent " \ 1456 "inlining") \ 1457 range(0, max_jint) \ 1458 \ 1459 develop(intx, InlineThrowCount, 50, \ 1460 "Force inlining of interpreted methods that throw this often") \ 1461 range(0, max_jint) \ 1462 \ 1463 develop(intx, InlineThrowMaxSize, 200, \ 1464 "Force inlining of throwing methods smaller than this") \ 1465 range(0, max_jint) \ 1466 \ 1467 product(size_t, MetaspaceSize, NOT_LP64(16 * M) LP64_ONLY(21 * M), \ 1468 "Initial threshold (in bytes) at which a garbage collection " \ 1469 "is done to reduce Metaspace usage") \ 1470 constraint(MetaspaceSizeConstraintFunc,AfterErgo) \ 1471 \ 1472 product(size_t, MaxMetaspaceSize, max_uintx, \ 1473 "Maximum size of Metaspaces (in bytes)") \ 1474 constraint(MaxMetaspaceSizeConstraintFunc,AfterErgo) \ 1475 \ 1476 product(size_t, CompressedClassSpaceSize, 1*G, \ 1477 "Maximum size of class area in Metaspace when compressed " \ 1478 "class pointers are used") \ 1479 range(1*M, 3*G) \ 1480 \ 1481 develop(size_t, CompressedClassSpaceBaseAddress, 0, \ 1482 "Force the class space to be allocated at this address or " \ 1483 "fails VM initialization (requires -Xshare=off.") \ 1484 \ 1485 product(ccstr, MetaspaceReclaimPolicy, "balanced", \ 1486 "options: balanced, aggressive, none") \ 1487 \ 1488 product(bool, PrintMetaspaceStatisticsAtExit, false, DIAGNOSTIC, \ 1489 "Print metaspace statistics upon VM exit.") \ 1490 \ 1491 product(bool, MetaspaceGuardAllocations, false, DIAGNOSTIC, \ 1492 "Metapace allocations are guarded.") \ 1493 \ 1494 product(bool, MetaspaceHandleDeallocations, true, DIAGNOSTIC, \ 1495 "Switch off Metapace deallocation handling.") \ 1496 \ 1497 product(uintx, MinHeapFreeRatio, 40, MANAGEABLE, \ 1498 "The minimum percentage of heap free after GC to avoid expansion."\ 1499 " For most GCs this applies to the old generation. In G1 and" \ 1500 " ParallelGC it applies to the whole heap.") \ 1501 range(0, 100) \ 1502 constraint(MinHeapFreeRatioConstraintFunc,AfterErgo) \ 1503 \ 1504 product(uintx, MaxHeapFreeRatio, 70, MANAGEABLE, \ 1505 "The maximum percentage of heap free after GC to avoid shrinking."\ 1506 " For most GCs this applies to the old generation. In G1 and" \ 1507 " ParallelGC it applies to the whole heap.") \ 1508 range(0, 100) \ 1509 constraint(MaxHeapFreeRatioConstraintFunc,AfterErgo) \ 1510 \ 1511 product(bool, ShrinkHeapInSteps, true, \ 1512 "When disabled, informs the GC to shrink the java heap directly" \ 1513 " to the target size at the next full GC rather than requiring" \ 1514 " smaller steps during multiple full GCs.") \ 1515 \ 1516 product(intx, SoftRefLRUPolicyMSPerMB, 1000, \ 1517 "Number of milliseconds per MB of free space in the heap") \ 1518 range(0, max_intx) \ 1519 constraint(SoftRefLRUPolicyMSPerMBConstraintFunc,AfterMemoryInit) \ 1520 \ 1521 product(size_t, MinHeapDeltaBytes, ScaleForWordSize(128*K), \ 1522 "The minimum change in heap space due to GC (in bytes)") \ 1523 range(0, max_uintx) \ 1524 \ 1525 product(size_t, MinMetaspaceExpansion, ScaleForWordSize(256*K), \ 1526 "The minimum expansion of Metaspace (in bytes)") \ 1527 range(0, max_uintx) \ 1528 \ 1529 product(uintx, MaxMetaspaceFreeRatio, 70, \ 1530 "The maximum percentage of Metaspace free after GC to avoid " \ 1531 "shrinking") \ 1532 range(0, 100) \ 1533 constraint(MaxMetaspaceFreeRatioConstraintFunc,AfterErgo) \ 1534 \ 1535 product(uintx, MinMetaspaceFreeRatio, 40, \ 1536 "The minimum percentage of Metaspace free after GC to avoid " \ 1537 "expansion") \ 1538 range(0, 99) \ 1539 constraint(MinMetaspaceFreeRatioConstraintFunc,AfterErgo) \ 1540 \ 1541 product(size_t, MaxMetaspaceExpansion, ScaleForWordSize(4*M), \ 1542 "The maximum expansion of Metaspace without full GC (in bytes)") \ 1543 range(0, max_uintx) \ 1544 \ 1545 /* stack parameters */ \ 1546 product_pd(intx, StackYellowPages, \ 1547 "Number of yellow zone (recoverable overflows) pages of size " \ 1548 "4KB. If pages are bigger yellow zone is aligned up.") \ 1549 range(MIN_STACK_YELLOW_PAGES, (DEFAULT_STACK_YELLOW_PAGES+5)) \ 1550 \ 1551 product_pd(intx, StackRedPages, \ 1552 "Number of red zone (unrecoverable overflows) pages of size " \ 1553 "4KB. If pages are bigger red zone is aligned up.") \ 1554 range(MIN_STACK_RED_PAGES, (DEFAULT_STACK_RED_PAGES+2)) \ 1555 \ 1556 product_pd(intx, StackReservedPages, \ 1557 "Number of reserved zone (reserved to annotated methods) pages" \ 1558 " of size 4KB. If pages are bigger reserved zone is aligned up.") \ 1559 range(MIN_STACK_RESERVED_PAGES, (DEFAULT_STACK_RESERVED_PAGES+10))\ 1560 \ 1561 product(bool, RestrictReservedStack, true, \ 1562 "Restrict @ReservedStackAccess to trusted classes") \ 1563 \ 1564 /* greater stack shadow pages can't generate instruction to bang stack */ \ 1565 product_pd(intx, StackShadowPages, \ 1566 "Number of shadow zone (for overflow checking) pages of size " \ 1567 "4KB. If pages are bigger shadow zone is aligned up. " \ 1568 "This should exceed the depth of the VM and native call stack.") \ 1569 range(MIN_STACK_SHADOW_PAGES, (DEFAULT_STACK_SHADOW_PAGES+30)) \ 1570 \ 1571 product_pd(intx, ThreadStackSize, \ 1572 "Thread Stack Size (in Kbytes)") \ 1573 range(0, 1 * M) \ 1574 \ 1575 product_pd(intx, VMThreadStackSize, \ 1576 "Non-Java Thread Stack Size (in Kbytes)") \ 1577 range(0, max_intx/(1 * K)) \ 1578 \ 1579 product_pd(intx, CompilerThreadStackSize, \ 1580 "Compiler Thread Stack Size (in Kbytes)") \ 1581 range(0, max_intx/(1 * K)) \ 1582 \ 1583 develop_pd(size_t, JVMInvokeMethodSlack, \ 1584 "Stack space (bytes) required for JVM_InvokeMethod to complete") \ 1585 \ 1586 /* code cache parameters */ \ 1587 product_pd(uintx, CodeCacheSegmentSize, EXPERIMENTAL, \ 1588 "Code cache segment size (in bytes) - smallest unit of " \ 1589 "allocation") \ 1590 range(1, 1024) \ 1591 constraint(CodeCacheSegmentSizeConstraintFunc, AfterErgo) \ 1592 \ 1593 develop_pd(intx, CodeEntryAlignment, \ 1594 "Code entry alignment for generated code (in bytes)") \ 1595 constraint(CodeEntryAlignmentConstraintFunc, AfterErgo) \ 1596 \ 1597 product_pd(intx, OptoLoopAlignment, \ 1598 "Align inner loops to zero relative to this modulus") \ 1599 range(1, 16) \ 1600 constraint(OptoLoopAlignmentConstraintFunc, AfterErgo) \ 1601 \ 1602 product_pd(uintx, InitialCodeCacheSize, \ 1603 "Initial code cache size (in bytes)") \ 1604 constraint(VMPageSizeConstraintFunc, AtParse) \ 1605 \ 1606 develop_pd(uintx, CodeCacheMinimumUseSpace, \ 1607 "Minimum code cache size (in bytes) required to start VM.") \ 1608 range(0, max_uintx) \ 1609 \ 1610 product(bool, SegmentedCodeCache, false, \ 1611 "Use a segmented code cache") \ 1612 \ 1613 product_pd(uintx, ReservedCodeCacheSize, \ 1614 "Reserved code cache size (in bytes) - maximum code cache size") \ 1615 constraint(VMPageSizeConstraintFunc, AtParse) \ 1616 \ 1617 product_pd(uintx, NonProfiledCodeHeapSize, \ 1618 "Size of code heap with non-profiled methods (in bytes)") \ 1619 range(0, max_uintx) \ 1620 \ 1621 product_pd(uintx, ProfiledCodeHeapSize, \ 1622 "Size of code heap with profiled methods (in bytes)") \ 1623 range(0, max_uintx) \ 1624 \ 1625 product_pd(uintx, NonNMethodCodeHeapSize, \ 1626 "Size of code heap with non-nmethods (in bytes)") \ 1627 constraint(VMPageSizeConstraintFunc, AtParse) \ 1628 \ 1629 product_pd(uintx, CodeCacheExpansionSize, \ 1630 "Code cache expansion size (in bytes)") \ 1631 range(32*K, max_uintx) \ 1632 \ 1633 product_pd(uintx, CodeCacheMinBlockLength, DIAGNOSTIC, \ 1634 "Minimum number of segments in a code cache block") \ 1635 range(1, 100) \ 1636 \ 1637 notproduct(bool, ExitOnFullCodeCache, false, \ 1638 "Exit the VM if we fill the code cache") \ 1639 \ 1640 product(bool, UseCodeCacheFlushing, true, \ 1641 "Remove cold/old nmethods from the code cache") \ 1642 \ 1643 product(double, SweeperThreshold, 0.5, \ 1644 "Threshold controlling when code cache sweeper is invoked." \ 1645 "Value is percentage of ReservedCodeCacheSize.") \ 1646 range(0.0, 100.0) \ 1647 \ 1648 product(uintx, StartAggressiveSweepingAt, 10, \ 1649 "Start aggressive sweeping if X[%] of the code cache is free." \ 1650 "Segmented code cache: X[%] of the non-profiled heap." \ 1651 "Non-segmented code cache: X[%] of the total code cache") \ 1652 range(0, 100) \ 1653 \ 1654 /* interpreter debugging */ \ 1655 develop(intx, BinarySwitchThreshold, 5, \ 1656 "Minimal number of lookupswitch entries for rewriting to binary " \ 1657 "switch") \ 1658 \ 1659 develop(intx, StopInterpreterAt, 0, \ 1660 "Stop interpreter execution at specified bytecode number") \ 1661 \ 1662 develop(intx, TraceBytecodesAt, 0, \ 1663 "Trace bytecodes starting with specified bytecode number") \ 1664 \ 1665 /* Priorities */ \ 1666 product_pd(bool, UseThreadPriorities, "Use native thread priorities") \ 1667 \ 1668 product(intx, ThreadPriorityPolicy, 0, \ 1669 "0 : Normal. "\ 1670 " VM chooses priorities that are appropriate for normal "\ 1671 " applications. "\ 1672 " On Windows applications are allowed to use higher native "\ 1673 " priorities. However, with ThreadPriorityPolicy=0, VM will "\ 1674 " not use the highest possible native priority, "\ 1675 " THREAD_PRIORITY_TIME_CRITICAL, as it may interfere with "\ 1676 " system threads. On Linux thread priorities are ignored "\ 1677 " because the OS does not support static priority in "\ 1678 " SCHED_OTHER scheduling class which is the only choice for "\ 1679 " non-root, non-realtime applications. "\ 1680 "1 : Aggressive. "\ 1681 " Java thread priorities map over to the entire range of "\ 1682 " native thread priorities. Higher Java thread priorities map "\ 1683 " to higher native thread priorities. This policy should be "\ 1684 " used with care, as sometimes it can cause performance "\ 1685 " degradation in the application and/or the entire system. On "\ 1686 " Linux/BSD/macOS this policy requires root privilege or an "\ 1687 " extended capability.") \ 1688 range(0, 1) \ 1689 \ 1690 product(bool, ThreadPriorityVerbose, false, \ 1691 "Print priority changes") \ 1692 \ 1693 product(intx, CompilerThreadPriority, -1, \ 1694 "The native priority at which compiler threads should run " \ 1695 "(-1 means no change)") \ 1696 range(min_jint, max_jint) \ 1697 \ 1698 product(intx, VMThreadPriority, -1, \ 1699 "The native priority at which the VM thread should run " \ 1700 "(-1 means no change)") \ 1701 range(-1, 127) \ 1702 \ 1703 product(intx, JavaPriority1_To_OSPriority, -1, \ 1704 "Map Java priorities to OS priorities") \ 1705 range(-1, 127) \ 1706 \ 1707 product(intx, JavaPriority2_To_OSPriority, -1, \ 1708 "Map Java priorities to OS priorities") \ 1709 range(-1, 127) \ 1710 \ 1711 product(intx, JavaPriority3_To_OSPriority, -1, \ 1712 "Map Java priorities to OS priorities") \ 1713 range(-1, 127) \ 1714 \ 1715 product(intx, JavaPriority4_To_OSPriority, -1, \ 1716 "Map Java priorities to OS priorities") \ 1717 range(-1, 127) \ 1718 \ 1719 product(intx, JavaPriority5_To_OSPriority, -1, \ 1720 "Map Java priorities to OS priorities") \ 1721 range(-1, 127) \ 1722 \ 1723 product(intx, JavaPriority6_To_OSPriority, -1, \ 1724 "Map Java priorities to OS priorities") \ 1725 range(-1, 127) \ 1726 \ 1727 product(intx, JavaPriority7_To_OSPriority, -1, \ 1728 "Map Java priorities to OS priorities") \ 1729 range(-1, 127) \ 1730 \ 1731 product(intx, JavaPriority8_To_OSPriority, -1, \ 1732 "Map Java priorities to OS priorities") \ 1733 range(-1, 127) \ 1734 \ 1735 product(intx, JavaPriority9_To_OSPriority, -1, \ 1736 "Map Java priorities to OS priorities") \ 1737 range(-1, 127) \ 1738 \ 1739 product(intx, JavaPriority10_To_OSPriority,-1, \ 1740 "Map Java priorities to OS priorities") \ 1741 range(-1, 127) \ 1742 \ 1743 product(bool, UseCriticalJavaThreadPriority, false, EXPERIMENTAL, \ 1744 "Java thread priority 10 maps to critical scheduling priority") \ 1745 \ 1746 product(bool, UseCriticalCompilerThreadPriority, false, EXPERIMENTAL, \ 1747 "Compiler thread(s) run at critical scheduling priority") \ 1748 \ 1749 develop(intx, NewCodeParameter, 0, \ 1750 "Testing Only: Create a dedicated integer parameter before " \ 1751 "putback") \ 1752 \ 1753 /* new oopmap storage allocation */ \ 1754 develop(intx, MinOopMapAllocation, 8, \ 1755 "Minimum number of OopMap entries in an OopMapSet") \ 1756 \ 1757 /* recompilation */ \ 1758 product_pd(intx, CompileThreshold, \ 1759 "number of interpreted method invocations before (re-)compiling") \ 1760 constraint(CompileThresholdConstraintFunc, AfterErgo) \ 1761 \ 1762 product_pd(bool, TieredCompilation, \ 1763 "Enable tiered compilation") \ 1764 \ 1765 /* Properties for Java libraries */ \ 1766 \ 1767 product(uint64_t, MaxDirectMemorySize, 0, \ 1768 "Maximum total size of NIO direct-buffer allocations") \ 1769 range(0, max_jlong) \ 1770 \ 1771 /* Flags used for temporary code during development */ \ 1772 \ 1773 product(bool, UseNewCode, false, DIAGNOSTIC, \ 1774 "Testing Only: Use the new version while testing") \ 1775 \ 1776 product(bool, UseNewCode2, false, DIAGNOSTIC, \ 1777 "Testing Only: Use the new version while testing") \ 1778 \ 1779 product(bool, UseNewCode3, false, DIAGNOSTIC, \ 1780 "Testing Only: Use the new version while testing") \ 1781 \ 1782 notproduct(bool, UseDebuggerErgo, false, \ 1783 "Debugging Only: Adjust the VM to be more debugger-friendly. " \ 1784 "Turns on the other UseDebuggerErgo* flags") \ 1785 \ 1786 notproduct(bool, UseDebuggerErgo1, false, \ 1787 "Debugging Only: Enable workarounds for debugger induced " \ 1788 "os::processor_id() >= os::processor_count() problems") \ 1789 \ 1790 notproduct(bool, UseDebuggerErgo2, false, \ 1791 "Debugging Only: Limit the number of spawned JVM threads") \ 1792 \ 1793 notproduct(bool, EnableJVMTIStackDepthAsserts, true, \ 1794 "Enable JVMTI asserts related to stack depth checks") \ 1795 \ 1796 /* flags for performance data collection */ \ 1797 \ 1798 product(bool, UsePerfData, true, \ 1799 "Flag to disable jvmstat instrumentation for performance testing "\ 1800 "and problem isolation purposes") \ 1801 \ 1802 product(bool, PerfDataSaveToFile, false, \ 1803 "Save PerfData memory to hsperfdata_<pid> file on exit") \ 1804 \ 1805 product(ccstr, PerfDataSaveFile, NULL, \ 1806 "Save PerfData memory to the specified absolute pathname. " \ 1807 "The string %p in the file name (if present) " \ 1808 "will be replaced by pid") \ 1809 \ 1810 product(intx, PerfDataSamplingInterval, 50, \ 1811 "Data sampling interval (in milliseconds)") \ 1812 range(PeriodicTask::min_interval, max_jint) \ 1813 constraint(PerfDataSamplingIntervalFunc, AfterErgo) \ 1814 \ 1815 product(bool, PerfDisableSharedMem, false, \ 1816 "Store performance data in standard memory") \ 1817 \ 1818 product(intx, PerfDataMemorySize, 32*K, \ 1819 "Size of performance data memory region. Will be rounded " \ 1820 "up to a multiple of the native os page size.") \ 1821 range(128, 32*64*K) \ 1822 \ 1823 product(intx, PerfMaxStringConstLength, 1024, \ 1824 "Maximum PerfStringConstant string length before truncation") \ 1825 range(32, 32*K) \ 1826 \ 1827 product(bool, PerfAllowAtExitRegistration, false, \ 1828 "Allow registration of atexit() methods") \ 1829 \ 1830 product(bool, PerfBypassFileSystemCheck, false, \ 1831 "Bypass Win32 file system criteria checks (Windows Only)") \ 1832 \ 1833 product(intx, UnguardOnExecutionViolation, 0, \ 1834 "Unguard page and retry on no-execute fault (Win32 only) " \ 1835 "0=off, 1=conservative, 2=aggressive") \ 1836 range(0, 2) \ 1837 \ 1838 /* Serviceability Support */ \ 1839 \ 1840 product(bool, ManagementServer, false, \ 1841 "Create JMX Management Server") \ 1842 \ 1843 product(bool, DisableAttachMechanism, false, \ 1844 "Disable mechanism that allows tools to attach to this VM") \ 1845 \ 1846 product(bool, StartAttachListener, false, \ 1847 "Always start Attach Listener at VM startup") \ 1848 \ 1849 product(bool, EnableDynamicAgentLoading, true, \ 1850 "Allow tools to load agents with the attach mechanism") \ 1851 \ 1852 product(bool, PrintConcurrentLocks, false, MANAGEABLE, \ 1853 "Print java.util.concurrent locks in thread dump") \ 1854 \ 1855 /* Shared spaces */ \ 1856 \ 1857 product(bool, UseSharedSpaces, true, \ 1858 "Use shared spaces for metadata") \ 1859 \ 1860 product(bool, VerifySharedSpaces, false, \ 1861 "Verify integrity of shared spaces") \ 1862 \ 1863 product(bool, RequireSharedSpaces, false, \ 1864 "Require shared spaces for metadata") \ 1865 \ 1866 product(bool, DumpSharedSpaces, false, \ 1867 "Special mode: JVM reads a class list, loads classes, builds " \ 1868 "shared spaces, and dumps the shared spaces to a file to be " \ 1869 "used in future JVM runs") \ 1870 \ 1871 product(bool, DynamicDumpSharedSpaces, false, \ 1872 "Dynamic archive") \ 1873 \ 1874 product(bool, RecordDynamicDumpInfo, false, \ 1875 "Record class info for jcmd VM.cds dynamic_dump") \ 1876 \ 1877 product(bool, PrintSharedArchiveAndExit, false, \ 1878 "Print shared archive file contents") \ 1879 \ 1880 product(bool, PrintSharedDictionary, false, \ 1881 "If PrintSharedArchiveAndExit is true, also print the shared " \ 1882 "dictionary") \ 1883 \ 1884 product(size_t, SharedBaseAddress, LP64_ONLY(32*G) \ 1885 NOT_LP64(LINUX_ONLY(2*G) NOT_LINUX(0)), \ 1886 "Address to allocate shared memory region for class data") \ 1887 range(0, SIZE_MAX) \ 1888 \ 1889 product(ccstr, SharedArchiveConfigFile, NULL, \ 1890 "Data to add to the CDS archive file") \ 1891 \ 1892 product(uintx, SharedSymbolTableBucketSize, 4, \ 1893 "Average number of symbols per bucket in shared table") \ 1894 range(2, 246) \ 1895 \ 1896 product(bool, AllowArchivingWithJavaAgent, false, DIAGNOSTIC, \ 1897 "Allow Java agent to be run with CDS dumping") \ 1898 \ 1899 product(bool, PrintMethodHandleStubs, false, DIAGNOSTIC, \ 1900 "Print generated stub code for method handles") \ 1901 \ 1902 product(bool, VerifyMethodHandles, trueInDebug, DIAGNOSTIC, \ 1903 "perform extra checks when constructing method handles") \ 1904 \ 1905 product(bool, ShowHiddenFrames, false, DIAGNOSTIC, \ 1906 "show method handle implementation frames (usually hidden)") \ 1907 \ 1908 product(bool, TrustFinalNonStaticFields, false, EXPERIMENTAL, \ 1909 "trust final non-static declarations for constant folding") \ 1910 \ 1911 product(bool, FoldStableValues, true, DIAGNOSTIC, \ 1912 "Optimize loads from stable fields (marked w/ @Stable)") \ 1913 \ 1914 product(int, UseBootstrapCallInfo, 1, DIAGNOSTIC, \ 1915 "0: when resolving InDy or ConDy, force all BSM arguments to be " \ 1916 "resolved before the bootstrap method is called; 1: when a BSM " \ 1917 "that may accept a BootstrapCallInfo is detected, use that API " \ 1918 "to pass BSM arguments, which allows the BSM to delay their " \ 1919 "resolution; 2+: stress test the BCI API by calling more BSMs " \ 1920 "via that API, instead of with the eagerly-resolved array.") \ 1921 \ 1922 product(bool, PauseAtStartup, false, DIAGNOSTIC, \ 1923 "Causes the VM to pause at startup time and wait for the pause " \ 1924 "file to be removed (default: ./vm.paused.<pid>)") \ 1925 \ 1926 product(ccstr, PauseAtStartupFile, NULL, DIAGNOSTIC, \ 1927 "The file to create and for whose removal to await when pausing " \ 1928 "at startup. (default: ./vm.paused.<pid>)") \ 1929 \ 1930 product(bool, PauseAtExit, false, DIAGNOSTIC, \ 1931 "Pause and wait for keypress on exit if a debugger is attached") \ 1932 \ 1933 product(bool, ExtendedDTraceProbes, false, \ 1934 "Enable performance-impacting dtrace probes") \ 1935 \ 1936 product(bool, DTraceMethodProbes, false, \ 1937 "Enable dtrace probes for method-entry and method-exit") \ 1938 \ 1939 product(bool, DTraceAllocProbes, false, \ 1940 "Enable dtrace probes for object allocation") \ 1941 \ 1942 product(bool, DTraceMonitorProbes, false, \ 1943 "Enable dtrace probes for monitor events") \ 1944 \ 1945 product(bool, RelaxAccessControlCheck, false, \ 1946 "Relax the access control checks in the verifier") \ 1947 \ 1948 product(uintx, StringTableSize, defaultStringTableSize, \ 1949 "Number of buckets in the interned String table " \ 1950 "(will be rounded to nearest higher power of 2)") \ 1951 range(minimumStringTableSize, 16777216ul /* 2^24 */) \ 1952 \ 1953 product(uintx, SymbolTableSize, defaultSymbolTableSize, EXPERIMENTAL, \ 1954 "Number of buckets in the JVM internal Symbol table") \ 1955 range(minimumSymbolTableSize, 16777216ul /* 2^24 */) \ 1956 \ 1957 product(bool, UseStringDeduplication, false, \ 1958 "Use string deduplication") \ 1959 \ 1960 product(uint, StringDeduplicationAgeThreshold, 3, \ 1961 "A string must reach this age (or be promoted to an old region) " \ 1962 "to be considered for deduplication") \ 1963 range(1, markWord::max_age) \ 1964 \ 1965 product(size_t, StringDeduplicationInitialTableSize, 500, EXPERIMENTAL, \ 1966 "Approximate initial number of buckets in the table") \ 1967 range(1, 1 * G) \ 1968 \ 1969 product(double, StringDeduplicationGrowTableLoad, 14.0, EXPERIMENTAL, \ 1970 "Entries per bucket above which the table should be expanded") \ 1971 range(0.1, 1000.0) \ 1972 \ 1973 product(double, StringDeduplicationShrinkTableLoad, 1.0, EXPERIMENTAL, \ 1974 "Entries per bucket below which the table should be shrunk") \ 1975 range(0.01, 100.0) \ 1976 \ 1977 product(double, StringDeduplicationTargetTableLoad, 7.0, EXPERIMENTAL, \ 1978 "Desired entries per bucket when resizing the table") \ 1979 range(0.01, 1000.0) \ 1980 \ 1981 product(size_t, StringDeduplicationCleanupDeadMinimum, 100, EXPERIMENTAL, \ 1982 "Minimum number of dead table entries for cleaning the table") \ 1983 \ 1984 product(int, StringDeduplicationCleanupDeadPercent, 5, EXPERIMENTAL, \ 1985 "Minimum percentage of dead table entries for cleaning the table") \ 1986 range(1, 100) \ 1987 \ 1988 product(bool, StringDeduplicationResizeALot, false, DIAGNOSTIC, \ 1989 "Force more frequent table resizing") \ 1990 \ 1991 product(uint64_t, StringDeduplicationHashSeed, 0, DIAGNOSTIC, \ 1992 "Seed for the table hashing function; 0 requests computed seed") \ 1993 \ 1994 product(bool, WhiteBoxAPI, false, DIAGNOSTIC, \ 1995 "Enable internal testing APIs") \ 1996 \ 1997 product(ccstr, DumpLoadedClassList, NULL, \ 1998 "Dump the names all loaded classes, that could be stored into " \ 1999 "the CDS archive, in the specified file") \ 2000 \ 2001 product(ccstr, SharedClassListFile, NULL, \ 2002 "Override the default CDS class list") \ 2003 \ 2004 product(ccstr, SharedArchiveFile, NULL, \ 2005 "Override the default location of the CDS archive file") \ 2006 \ 2007 product(ccstr, ArchiveClassesAtExit, NULL, \ 2008 "The path and name of the dynamic archive file") \ 2009 \ 2010 product(ccstr, ExtraSharedClassListFile, NULL, \ 2011 "Extra classlist for building the CDS archive file") \ 2012 \ 2013 product(intx, ArchiveRelocationMode, 0, DIAGNOSTIC, \ 2014 "(0) first map at preferred address, and if " \ 2015 "unsuccessful, map at alternative address (default); " \ 2016 "(1) always map at alternative address; " \ 2017 "(2) always map at preferred address, and if unsuccessful, " \ 2018 "do not map the archive") \ 2019 range(0, 2) \ 2020 \ 2021 product(size_t, ArrayAllocatorMallocLimit, (size_t)-1, EXPERIMENTAL, \ 2022 "Allocation less than this value will be allocated " \ 2023 "using malloc. Larger allocations will use mmap.") \ 2024 \ 2025 product(bool, AlwaysAtomicAccesses, false, EXPERIMENTAL, \ 2026 "Accesses to all variables should always be atomic") \ 2027 \ 2028 product(bool, UseUnalignedAccesses, false, DIAGNOSTIC, \ 2029 "Use unaligned memory accesses in Unsafe") \ 2030 \ 2031 product_pd(bool, PreserveFramePointer, \ 2032 "Use the FP register for holding the frame pointer " \ 2033 "and not as a general purpose register.") \ 2034 \ 2035 product(size_t, AsyncLogBufferSize, 2*M, \ 2036 "Memory budget (in bytes) for the buffer of Asynchronous " \ 2037 "Logging (-Xlog:async).") \ 2038 range(100*K, 50*M) \ 2039 \ 2040 product(bool, CheckIntrinsics, true, DIAGNOSTIC, \ 2041 "When a class C is loaded, check that " \ 2042 "(1) all intrinsics defined by the VM for class C are present "\ 2043 "in the loaded class file and are marked with the " \ 2044 "@IntrinsicCandidate annotation, that " \ 2045 "(2) there is an intrinsic registered for all loaded methods " \ 2046 "that are annotated with the @IntrinsicCandidate annotation, " \ 2047 "and that " \ 2048 "(3) no orphan methods exist for class C (i.e., methods for " \ 2049 "which the VM declares an intrinsic but that are not declared "\ 2050 "in the loaded class C. " \ 2051 "Check (3) is available only in debug builds.") \ 2052 \ 2053 product_pd(intx, InitArrayShortSize, DIAGNOSTIC, \ 2054 "Threshold small size (in bytes) for clearing arrays. " \ 2055 "Anything this size or smaller may get converted to discrete " \ 2056 "scalar stores.") \ 2057 range(0, max_intx) \ 2058 constraint(InitArrayShortSizeConstraintFunc, AfterErgo) \ 2059 \ 2060 product(ccstr, AllocateHeapAt, NULL, \ 2061 "Path to the directory where a temporary file will be created " \ 2062 "to use as the backing store for Java Heap.") \ 2063 \ 2064 develop(int, VerifyMetaspaceInterval, DEBUG_ONLY(500) NOT_DEBUG(0), \ 2065 "Run periodic metaspace verifications (0 - none, " \ 2066 "1 - always, >1 every nth interval)") \ 2067 \ 2068 product(bool, ShowRegistersOnAssert, true, DIAGNOSTIC, \ 2069 "On internal errors, include registers in error report.") \ 2070 \ 2071 product(bool, UseSwitchProfiling, true, DIAGNOSTIC, \ 2072 "leverage profiling for table/lookup switch") \ 2073 \ 2074 develop(bool, TraceMemoryWriteback, false, \ 2075 "Trace memory writeback operations") \ 2076 \ 2077 JFR_ONLY(product(bool, FlightRecorder, false, \ 2078 "(Deprecated) Enable Flight Recorder")) \ 2079 \ 2080 JFR_ONLY(product(ccstr, FlightRecorderOptions, NULL, \ 2081 "Flight Recorder options")) \ 2082 \ 2083 JFR_ONLY(product(ccstr, StartFlightRecording, NULL, \ 2084 "Start flight recording with options")) \ 2085 \ 2086 product(bool, UseFastUnorderedTimeStamps, false, EXPERIMENTAL, \ 2087 "Use platform unstable time where supported for timestamps only") \ 2088 \ 2089 product(bool, UseEmptySlotsInSupers, true, \ 2090 "Allow allocating fields in empty slots of super-classes") \ 2091 \ 2092 product(bool, DeoptimizeNMethodBarriersALot, false, DIAGNOSTIC, \ 2093 "Make nmethod barriers deoptimise a lot.") \ 2094 \ 2095 develop(bool, VerifyCrossModifyFence, \ 2096 false AARCH64_ONLY(DEBUG_ONLY(||true)), \ 2097 "Mark all threads after a safepoint, and clear on a modify " \ 2098 "fence. Add cleanliness checks.") \ 2099 \ 2100 product(bool, HeapObjectStats, false, DIAGNOSTIC, \ 2101 "Enable gathering of heap object statistics") \ 2102 \ 2103 product(size_t, HeapObjectStatsSamplingInterval, 500, DIAGNOSTIC, \ 2104 "Heap object statistics sampling interval (ms)") \ 2105 \ 2106 product(int, LockingMode, LM_LEGACY, EXPERIMENTAL, \ 2107 "Select locking mode: " \ 2108 "0: monitors only (LM_MONITOR), " \ 2109 "1: monitors & legacy stack-locking (LM_LEGACY, default), " \ 2110 "2: monitors & new lightweight locking (LM_LIGHTWEIGHT)") \ 2111 range(0, 2) \ 2112 \ 2113 develop(bool, TraceOptimizedUpcallStubs, false, \ 2114 "Trace optimized upcall stub generation") \ 2115 2116 // end of RUNTIME_FLAGS 2117 2118 DECLARE_FLAGS(LP64_RUNTIME_FLAGS) 2119 DECLARE_ARCH_FLAGS(ARCH_FLAGS) 2120 DECLARE_FLAGS(RUNTIME_FLAGS) 2121 DECLARE_FLAGS(RUNTIME_OS_FLAGS) 2122 2123 #endif // SHARE_RUNTIME_GLOBALS_HPP