1 /* 2 * Copyright (c) 1997, 2023, 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 may not be 71 // an officially supported part of a product, but may be 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 // Refer to the documentation of any products using this code for details 79 // on support and fitness for production. 80 // Like the UnlockDiagnosticVMOptions flag above, there is a corresponding 81 // UnlockExperimentalVMOptions flag, which allows the control and 82 // modification of the experimental flags. 83 // 84 // Nota bene: neither diagnostic nor experimental options should be used casually, 85 // Refer to the documentation of any products using this code for details. 86 // 87 // MANAGEABLE flags are writeable external product flags. 88 // They are dynamically writeable through the JDK management interface 89 // (com.sun.management.HotSpotDiagnosticMXBean API) and also through JConsole. 90 // These flags are external exported interface (see CCC). The list of 91 // manageable flags can be queried programmatically through the management 92 // interface. 93 // 94 // A flag can be made as "manageable" only if 95 // - the flag is defined in a CCC as an external exported interface. 96 // - the VM implementation supports dynamic setting of the flag. 97 // This implies that the VM must *always* query the flag variable 98 // and not reuse state related to the flag state at any given time. 99 // - you want the flag to be queried programmatically by the customers. 100 // 101 102 // 103 // range is a macro that will expand to min and max arguments for range 104 // checking code if provided - see jvmFlagLimit.hpp 105 // 106 // constraint is a macro that will expand to custom function call 107 // for constraint checking if provided - see jvmFlagLimit.hpp 108 109 // Default and minimum StringTable and SymbolTable size values 110 // Must be powers of 2 111 const size_t defaultStringTableSize = NOT_LP64(1024) LP64_ONLY(65536); 112 const size_t minimumStringTableSize = 128; 113 const size_t defaultSymbolTableSize = 32768; // 2^15 114 const size_t minimumSymbolTableSize = 1024; 115 116 #ifdef _LP64 117 #define LP64_RUNTIME_FLAGS(develop, \ 118 develop_pd, \ 119 product, \ 120 product_pd, \ 121 notproduct, \ 122 range, \ 123 constraint) \ 124 \ 125 product(bool, UseCompressedOops, false, \ 126 "Use 32-bit object references in 64-bit VM. " \ 127 "lp64_product means flag is always constant in 32 bit VM") \ 128 \ 129 product(bool, UseCompressedClassPointers, false, \ 130 "Use 32-bit class pointers in 64-bit VM. " \ 131 "lp64_product means flag is always constant in 32 bit VM") \ 132 \ 133 product(intx, ObjectAlignmentInBytes, 8, \ 134 "Default object alignment in bytes, 8 is minimum") \ 135 range(8, 256) \ 136 constraint(ObjectAlignmentInBytesConstraintFunc, AtParse) 137 138 #else 139 // !_LP64 140 141 #define LP64_RUNTIME_FLAGS(develop, \ 142 develop_pd, \ 143 product, \ 144 product_pd, \ 145 notproduct, \ 146 range, \ 147 constraint) 148 const bool UseCompressedOops = false; 149 const bool UseCompressedClassPointers = false; 150 const intx ObjectAlignmentInBytes = 8; 151 152 #endif // _LP64 153 154 #define RUNTIME_FLAGS(develop, \ 155 develop_pd, \ 156 product, \ 157 product_pd, \ 158 notproduct, \ 159 range, \ 160 constraint) \ 161 \ 162 notproduct(bool, CheckCompressedOops, true, \ 163 "Generate checks in encoding/decoding code in debug VM") \ 164 \ 165 product(uintx, HeapSearchSteps, 3 PPC64_ONLY(+17), \ 166 "Heap allocation steps through preferred address regions to find" \ 167 " where it can allocate the heap. Number of steps to take per " \ 168 "region.") \ 169 range(1, max_uintx) \ 170 \ 171 product(uint, HandshakeTimeout, 0, DIAGNOSTIC, \ 172 "If nonzero set a timeout in milliseconds for handshakes") \ 173 \ 174 product(bool, AlwaysSafeConstructors, false, EXPERIMENTAL, \ 175 "Force safe construction, as if all fields are final.") \ 176 \ 177 product(bool, UnlockDiagnosticVMOptions, trueInDebug, DIAGNOSTIC, \ 178 "Enable normal processing of flags relating to field diagnostics")\ 179 \ 180 product(bool, UnlockExperimentalVMOptions, false, EXPERIMENTAL, \ 181 "Enable normal processing of flags relating to experimental " \ 182 "features") \ 183 \ 184 product(bool, JavaMonitorsInStackTrace, true, \ 185 "Print information about Java monitor locks when the stacks are " \ 186 "dumped") \ 187 \ 188 product_pd(bool, UseLargePages, \ 189 "Use large page memory") \ 190 \ 191 product_pd(bool, UseLargePagesIndividualAllocation, \ 192 "Allocate large pages individually for better affinity") \ 193 \ 194 develop(bool, LargePagesIndividualAllocationInjectError, false, \ 195 "Fail large pages individual allocation") \ 196 \ 197 product(bool, UseNUMA, false, \ 198 "Use NUMA if available") \ 199 \ 200 product(bool, UseNUMAInterleaving, false, \ 201 "Interleave memory across NUMA nodes if available") \ 202 \ 203 product(size_t, NUMAInterleaveGranularity, 2*M, \ 204 "Granularity to use for NUMA interleaving on Windows OS") \ 205 constraint(NUMAInterleaveGranularityConstraintFunc, AtParse) \ 206 \ 207 product(uintx, NUMAChunkResizeWeight, 20, \ 208 "Percentage (0-100) used to weight the current sample when " \ 209 "computing exponentially decaying average for " \ 210 "AdaptiveNUMAChunkSizing") \ 211 range(0, 100) \ 212 \ 213 product(size_t, NUMASpaceResizeRate, 1*G, \ 214 "Do not reallocate more than this amount per collection") \ 215 range(0, max_uintx) \ 216 \ 217 product(bool, UseAdaptiveNUMAChunkSizing, true, \ 218 "Enable adaptive chunk sizing for NUMA") \ 219 \ 220 product(bool, NUMAStats, false, \ 221 "Print NUMA stats in detailed heap information") \ 222 \ 223 product(uintx, NUMAPageScanRate, 256, \ 224 "Maximum number of pages to include in the page scan procedure") \ 225 range(0, max_uintx) \ 226 \ 227 product(bool, UseAES, false, \ 228 "Control whether AES instructions are used when available") \ 229 \ 230 product(bool, UseFMA, false, \ 231 "Control whether FMA instructions are used when available") \ 232 \ 233 product(bool, UseSHA, false, \ 234 "Control whether SHA instructions are used when available") \ 235 \ 236 product(bool, UseGHASHIntrinsics, false, DIAGNOSTIC, \ 237 "Use intrinsics for GHASH versions of crypto") \ 238 \ 239 product(bool, UseBASE64Intrinsics, false, \ 240 "Use intrinsics for java.util.Base64") \ 241 \ 242 product(size_t, LargePageSizeInBytes, 0, \ 243 "Maximum large page size used (0 will use the default large " \ 244 "page size for the environment as the maximum)") \ 245 range(0, max_uintx) \ 246 \ 247 product(size_t, LargePageHeapSizeThreshold, 128*M, \ 248 "Use large pages if maximum heap is at least this big") \ 249 range(0, max_uintx) \ 250 \ 251 product(bool, ForceTimeHighResolution, false, \ 252 "Using high time resolution (for Win32 only)") \ 253 \ 254 develop(bool, TracePcPatching, false, \ 255 "Trace usage of frame::patch_pc") \ 256 \ 257 develop(bool, TraceRelocator, false, \ 258 "Trace the bytecode relocator") \ 259 \ 260 \ 261 product(bool, SafepointALot, false, DIAGNOSTIC, \ 262 "Generate a lot of safepoints. This works with " \ 263 "GuaranteedSafepointInterval") \ 264 \ 265 product(bool, HandshakeALot, false, DIAGNOSTIC, \ 266 "Generate a lot of handshakes. This works with " \ 267 "GuaranteedSafepointInterval") \ 268 \ 269 product_pd(bool, BackgroundCompilation, \ 270 "A thread requesting compilation is not blocked during " \ 271 "compilation") \ 272 \ 273 product(bool, MethodFlushing, true, \ 274 "Reclamation of zombie and not-entrant methods") \ 275 \ 276 develop(bool, VerifyStack, false, \ 277 "Verify stack of each thread when it is entering a runtime call") \ 278 \ 279 product(bool, ForceUnreachable, false, DIAGNOSTIC, \ 280 "Make all non code cache addresses to be unreachable by " \ 281 "forcing use of 64bit literal fixups") \ 282 \ 283 develop(bool, TraceDerivedPointers, false, \ 284 "Trace traversal of derived pointers on stack") \ 285 \ 286 notproduct(bool, TraceCodeBlobStacks, false, \ 287 "Trace stack-walk of codeblobs") \ 288 \ 289 notproduct(bool, PrintRewrites, false, \ 290 "Print methods that are being rewritten") \ 291 \ 292 product(bool, UseInlineCaches, true, \ 293 "Use Inline Caches for virtual calls ") \ 294 \ 295 product(size_t, InlineCacheBufferSize, 10*K, EXPERIMENTAL, \ 296 "InlineCacheBuffer size") \ 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 product(uintx, ProcessDistributionStride, 4, \ 924 "Stride through processors when distributing processes") \ 925 range(0, max_juint) \ 926 \ 927 develop(bool, TraceFinalizerRegistration, false, \ 928 "Trace registration of final references") \ 929 \ 930 product(bool, IgnoreEmptyClassPaths, false, \ 931 "Ignore empty path elements in -classpath") \ 932 \ 933 product(bool, PrintHeapAtSIGBREAK, true, \ 934 "Print heap layout in response to SIGBREAK") \ 935 \ 936 product(bool, PrintClassHistogram, false, MANAGEABLE, \ 937 "Print a histogram of class instances") \ 938 \ 939 product(double, ObjectCountCutOffPercent, 0.5, EXPERIMENTAL, \ 940 "The percentage of the used heap that the instances of a class " \ 941 "must occupy for the class to generate a trace event") \ 942 range(0.0, 100.0) \ 943 \ 944 /* JVMTI heap profiling */ \ 945 \ 946 product(bool, VerifyBeforeIteration, false, DIAGNOSTIC, \ 947 "Verify memory system before JVMTI iteration") \ 948 \ 949 /* compiler */ \ 950 \ 951 /* notice: the max range value here is max_jint, not max_intx */ \ 952 /* because of overflow issue */ \ 953 product(intx, CICompilerCount, CI_COMPILER_COUNT, \ 954 "Number of compiler threads to run") \ 955 range(0, max_jint) \ 956 constraint(CICompilerCountConstraintFunc, AfterErgo) \ 957 \ 958 product(bool, UseDynamicNumberOfCompilerThreads, true, \ 959 "Dynamically choose the number of parallel compiler threads") \ 960 \ 961 product(bool, ReduceNumberOfCompilerThreads, true, DIAGNOSTIC, \ 962 "Reduce the number of parallel compiler threads when they " \ 963 "are not used") \ 964 \ 965 product(bool, TraceCompilerThreads, false, DIAGNOSTIC, \ 966 "Trace creation and removal of compiler threads") \ 967 \ 968 develop(bool, InjectCompilerCreationFailure, false, \ 969 "Inject thread creation failures for " \ 970 "UseDynamicNumberOfCompilerThreads") \ 971 \ 972 develop(bool, GenerateSynchronizationCode, true, \ 973 "generate locking/unlocking code for synchronized methods and " \ 974 "monitors") \ 975 \ 976 develop(bool, GenerateRangeChecks, true, \ 977 "Generate range checks for array accesses") \ 978 \ 979 product_pd(bool, ImplicitNullChecks, DIAGNOSTIC, \ 980 "Generate code for implicit null checks") \ 981 \ 982 product_pd(bool, TrapBasedNullChecks, \ 983 "Generate code for null checks that uses a cmp and trap " \ 984 "instruction raising SIGTRAP. This is only used if an access to" \ 985 "null (+offset) will not raise a SIGSEGV, i.e.," \ 986 "ImplicitNullChecks don't work (PPC64).") \ 987 \ 988 product(bool, EnableThreadSMRStatistics, trueInDebug, DIAGNOSTIC, \ 989 "Enable Thread SMR Statistics") \ 990 \ 991 product(bool, UseNotificationThread, true, \ 992 "Use Notification Thread") \ 993 \ 994 product(bool, Inline, true, \ 995 "Enable inlining") \ 996 \ 997 product(bool, ClipInlining, true, \ 998 "Clip inlining if aggregate method exceeds DesiredMethodLimit") \ 999 \ 1000 develop(bool, UseCHA, true, \ 1001 "Enable CHA") \ 1002 \ 1003 product(bool, UseVtableBasedCHA, true, DIAGNOSTIC, \ 1004 "Use vtable information during CHA") \ 1005 \ 1006 product(bool, UseTypeProfile, true, \ 1007 "Check interpreter profile for historically monomorphic calls") \ 1008 \ 1009 product(bool, PrintInlining, false, DIAGNOSTIC, \ 1010 "Print inlining optimizations") \ 1011 \ 1012 product(bool, UsePopCountInstruction, false, \ 1013 "Use population count instruction") \ 1014 \ 1015 develop(bool, EagerInitialization, false, \ 1016 "Eagerly initialize classes if possible") \ 1017 \ 1018 product(bool, LogTouchedMethods, false, DIAGNOSTIC, \ 1019 "Log methods which have been ever touched in runtime") \ 1020 \ 1021 product(bool, PrintTouchedMethodsAtExit, false, DIAGNOSTIC, \ 1022 "Print all methods that have been ever touched in runtime") \ 1023 \ 1024 develop(bool, TraceMethodReplacement, false, \ 1025 "Print when methods are replaced do to recompilation") \ 1026 \ 1027 develop(bool, PrintMethodFlushing, false, \ 1028 "Print the nmethods being flushed") \ 1029 \ 1030 product(bool, PrintMethodFlushingStatistics, false, DIAGNOSTIC, \ 1031 "print statistics about method flushing") \ 1032 \ 1033 product(intx, HotMethodDetectionLimit, 100000, DIAGNOSTIC, \ 1034 "Number of compiled code invocations after which " \ 1035 "the method is considered as hot by the flusher") \ 1036 range(1, max_jint) \ 1037 \ 1038 product(intx, MinPassesBeforeFlush, 10, DIAGNOSTIC, \ 1039 "Minimum number of sweeper passes before an nmethod " \ 1040 "can be flushed") \ 1041 range(0, max_intx) \ 1042 \ 1043 product(bool, UseCodeAging, true, \ 1044 "Insert counter to detect warm methods") \ 1045 \ 1046 product(bool, StressCodeAging, false, DIAGNOSTIC, \ 1047 "Start with counters compiled in") \ 1048 \ 1049 develop(bool, StressCodeBuffers, false, \ 1050 "Exercise code buffer expansion and other rare state changes") \ 1051 \ 1052 product(bool, DebugNonSafepoints, trueInDebug, DIAGNOSTIC, \ 1053 "Generate extra debugging information for non-safepoints in " \ 1054 "nmethods") \ 1055 \ 1056 product(bool, PrintVMOptions, false, \ 1057 "Print flags that appeared on the command line") \ 1058 \ 1059 product(bool, IgnoreUnrecognizedVMOptions, false, \ 1060 "Ignore unrecognized VM options") \ 1061 \ 1062 product(bool, PrintCommandLineFlags, false, \ 1063 "Print flags specified on command line or set by ergonomics") \ 1064 \ 1065 product(bool, PrintFlagsInitial, false, \ 1066 "Print all VM flags before argument processing and exit VM") \ 1067 \ 1068 product(bool, PrintFlagsFinal, false, \ 1069 "Print all VM flags after argument and ergonomic processing") \ 1070 \ 1071 notproduct(bool, PrintFlagsWithComments, false, \ 1072 "Print all VM flags with default values and descriptions and " \ 1073 "exit") \ 1074 \ 1075 product(bool, PrintFlagsRanges, false, \ 1076 "Print VM flags and their ranges") \ 1077 \ 1078 product(bool, SerializeVMOutput, true, DIAGNOSTIC, \ 1079 "Use a mutex to serialize output to tty and LogFile") \ 1080 \ 1081 product(bool, DisplayVMOutput, true, DIAGNOSTIC, \ 1082 "Display all VM output on the tty, independently of LogVMOutput") \ 1083 \ 1084 product(bool, LogVMOutput, false, DIAGNOSTIC, \ 1085 "Save VM output to LogFile") \ 1086 \ 1087 product(ccstr, LogFile, NULL, DIAGNOSTIC, \ 1088 "If LogVMOutput or LogCompilation is on, save VM output to " \ 1089 "this file [default: ./hotspot_pid%p.log] (%p replaced with pid)")\ 1090 \ 1091 product(ccstr, ErrorFile, NULL, \ 1092 "If an error occurs, save the error data to this file " \ 1093 "[default: ./hs_err_pid%p.log] (%p replaced with pid)") \ 1094 \ 1095 product(bool, ExtensiveErrorReports, \ 1096 PRODUCT_ONLY(false) NOT_PRODUCT(true), \ 1097 "Error reports are more extensive.") \ 1098 \ 1099 product(bool, DisplayVMOutputToStderr, false, \ 1100 "If DisplayVMOutput is true, display all VM output to stderr") \ 1101 \ 1102 product(bool, DisplayVMOutputToStdout, false, \ 1103 "If DisplayVMOutput is true, display all VM output to stdout") \ 1104 \ 1105 product(bool, ErrorFileToStderr, false, \ 1106 "If true, error data is printed to stderr instead of a file") \ 1107 \ 1108 product(bool, ErrorFileToStdout, false, \ 1109 "If true, error data is printed to stdout instead of a file") \ 1110 \ 1111 product(bool, UseHeavyMonitors, false, \ 1112 "use heavyweight instead of lightweight Java monitors") \ 1113 \ 1114 product(bool, PrintStringTableStatistics, false, \ 1115 "print statistics about the StringTable and SymbolTable") \ 1116 \ 1117 product(bool, VerifyStringTableAtExit, false, DIAGNOSTIC, \ 1118 "verify StringTable contents at exit") \ 1119 \ 1120 notproduct(bool, PrintSymbolTableSizeHistogram, false, \ 1121 "print histogram of the symbol table") \ 1122 \ 1123 product(ccstr, AbortVMOnException, NULL, DIAGNOSTIC, \ 1124 "Call fatal if this exception is thrown. Example: " \ 1125 "java -XX:AbortVMOnException=java.lang.NullPointerException Foo") \ 1126 \ 1127 product(ccstr, AbortVMOnExceptionMessage, NULL, DIAGNOSTIC, \ 1128 "Call fatal if the exception pointed by AbortVMOnException " \ 1129 "has this message") \ 1130 \ 1131 develop(bool, DebugVtables, false, \ 1132 "add debugging code to vtable dispatch") \ 1133 \ 1134 notproduct(bool, PrintVtableStats, false, \ 1135 "print vtables stats at end of run") \ 1136 \ 1137 develop(bool, TraceCreateZombies, false, \ 1138 "trace creation of zombie nmethods") \ 1139 \ 1140 product(bool, RangeCheckElimination, true, \ 1141 "Eliminate range checks") \ 1142 \ 1143 develop_pd(bool, UncommonNullCast, \ 1144 "track occurrences of null in casts; adjust compiler tactics") \ 1145 \ 1146 develop(bool, TypeProfileCasts, true, \ 1147 "treat casts like calls for purposes of type profiling") \ 1148 \ 1149 develop(bool, TraceLivenessGen, false, \ 1150 "Trace the generation of liveness analysis information") \ 1151 \ 1152 notproduct(bool, TraceLivenessQuery, false, \ 1153 "Trace queries of liveness analysis information") \ 1154 \ 1155 notproduct(bool, CollectIndexSetStatistics, false, \ 1156 "Collect information about IndexSets") \ 1157 \ 1158 develop(intx, FastAllocateSizeLimit, 128*K, \ 1159 /* Note: This value is zero mod 1<<13 for a cheap sparc set. */ \ 1160 "Inline allocations larger than this in doublewords must go slow")\ 1161 \ 1162 product_pd(bool, CompactStrings, \ 1163 "Enable Strings to use single byte chars in backing store") \ 1164 \ 1165 product_pd(uintx, TypeProfileLevel, \ 1166 "=XYZ, with Z: Type profiling of arguments at call; " \ 1167 "Y: Type profiling of return value at call; " \ 1168 "X: Type profiling of parameters to methods; " \ 1169 "X, Y and Z in 0=off ; 1=jsr292 only; 2=all methods") \ 1170 constraint(TypeProfileLevelConstraintFunc, AfterErgo) \ 1171 \ 1172 product(intx, TypeProfileArgsLimit, 2, \ 1173 "max number of call arguments to consider for type profiling") \ 1174 range(0, 16) \ 1175 \ 1176 product(intx, TypeProfileParmsLimit, 2, \ 1177 "max number of incoming parameters to consider for type profiling"\ 1178 ", -1 for all") \ 1179 range(-1, 64) \ 1180 \ 1181 /* statistics */ \ 1182 develop(bool, CountCompiledCalls, false, \ 1183 "Count method invocations") \ 1184 \ 1185 notproduct(bool, ICMissHistogram, false, \ 1186 "Produce histogram of IC misses") \ 1187 \ 1188 /* interpreter */ \ 1189 product_pd(bool, RewriteBytecodes, \ 1190 "Allow rewriting of bytecodes (bytecodes are not immutable)") \ 1191 \ 1192 product_pd(bool, RewriteFrequentPairs, \ 1193 "Rewrite frequently used bytecode pairs into a single bytecode") \ 1194 \ 1195 product(bool, PrintInterpreter, false, DIAGNOSTIC, \ 1196 "Print the generated interpreter code") \ 1197 \ 1198 product(bool, UseInterpreter, true, \ 1199 "Use interpreter for non-compiled methods") \ 1200 \ 1201 develop(bool, UseFastSignatureHandlers, true, \ 1202 "Use fast signature handlers for native calls") \ 1203 \ 1204 product(bool, UseLoopCounter, true, \ 1205 "Increment invocation counter on backward branch") \ 1206 \ 1207 product_pd(bool, UseOnStackReplacement, \ 1208 "Use on stack replacement, calls runtime if invoc. counter " \ 1209 "overflows in loop") \ 1210 \ 1211 notproduct(bool, TraceOnStackReplacement, false, \ 1212 "Trace on stack replacement") \ 1213 \ 1214 product_pd(bool, PreferInterpreterNativeStubs, \ 1215 "Use always interpreter stubs for native methods invoked via " \ 1216 "interpreter") \ 1217 \ 1218 develop(bool, CountBytecodes, false, \ 1219 "Count number of bytecodes executed") \ 1220 \ 1221 develop(bool, PrintBytecodeHistogram, false, \ 1222 "Print histogram of the executed bytecodes") \ 1223 \ 1224 develop(bool, PrintBytecodePairHistogram, false, \ 1225 "Print histogram of the executed bytecode pairs") \ 1226 \ 1227 product(bool, PrintSignatureHandlers, false, DIAGNOSTIC, \ 1228 "Print code generated for native method signature handlers") \ 1229 \ 1230 develop(bool, VerifyOops, false, \ 1231 "Do plausibility checks for oops") \ 1232 \ 1233 develop(bool, CheckUnhandledOops, false, \ 1234 "Check for unhandled oops in VM code") \ 1235 \ 1236 develop(bool, VerifyJNIFields, trueInDebug, \ 1237 "Verify jfieldIDs for instance fields") \ 1238 \ 1239 notproduct(bool, VerifyJNIEnvThread, false, \ 1240 "Verify JNIEnv.thread == Thread::current() when entering VM " \ 1241 "from JNI") \ 1242 \ 1243 develop(bool, VerifyFPU, false, \ 1244 "Verify FPU state (check for NaN's, etc.)") \ 1245 \ 1246 develop(bool, VerifyThread, false, \ 1247 "Watch the thread register for corruption (SPARC only)") \ 1248 \ 1249 develop(bool, VerifyActivationFrameSize, false, \ 1250 "Verify that activation frame didn't become smaller than its " \ 1251 "minimal size") \ 1252 \ 1253 develop(bool, TraceFrequencyInlining, false, \ 1254 "Trace frequency based inlining") \ 1255 \ 1256 develop_pd(bool, InlineIntrinsics, \ 1257 "Inline intrinsics that can be statically resolved") \ 1258 \ 1259 product_pd(bool, ProfileInterpreter, \ 1260 "Profile at the bytecode level during interpretation") \ 1261 \ 1262 develop_pd(bool, ProfileTraps, \ 1263 "Profile deoptimization traps at the bytecode level") \ 1264 \ 1265 product(intx, ProfileMaturityPercentage, 20, \ 1266 "number of method invocations/branches (expressed as % of " \ 1267 "CompileThreshold) before using the method's profile") \ 1268 range(0, 100) \ 1269 \ 1270 product(bool, PrintMethodData, false, DIAGNOSTIC, \ 1271 "Print the results of +ProfileInterpreter at end of run") \ 1272 \ 1273 develop(bool, VerifyDataPointer, trueInDebug, \ 1274 "Verify the method data pointer during interpreter profiling") \ 1275 \ 1276 notproduct(bool, CrashGCForDumpingJavaThread, false, \ 1277 "Manually make GC thread crash then dump java stack trace; " \ 1278 "Test only") \ 1279 \ 1280 /* compilation */ \ 1281 product(bool, UseCompiler, true, \ 1282 "Use Just-In-Time compilation") \ 1283 \ 1284 product(bool, UseCounterDecay, true, \ 1285 "Adjust recompilation counters") \ 1286 \ 1287 develop(intx, CounterHalfLifeTime, 30, \ 1288 "Half-life time of invocation counters (in seconds)") \ 1289 \ 1290 develop(intx, CounterDecayMinIntervalLength, 500, \ 1291 "The minimum interval (in milliseconds) between invocation of " \ 1292 "CounterDecay") \ 1293 \ 1294 product(bool, AlwaysCompileLoopMethods, false, \ 1295 "When using recompilation, never interpret methods " \ 1296 "containing loops") \ 1297 \ 1298 product(intx, AllocatePrefetchStyle, 1, \ 1299 "0 = no prefetch, " \ 1300 "1 = generate prefetch instructions for each allocation, " \ 1301 "2 = use TLAB watermark to gate allocation prefetch, " \ 1302 "3 = generate one prefetch instruction per cache line") \ 1303 range(0, 3) \ 1304 \ 1305 product(intx, AllocatePrefetchDistance, -1, \ 1306 "Distance to prefetch ahead of allocation pointer. " \ 1307 "-1: use system-specific value (automatically determined") \ 1308 constraint(AllocatePrefetchDistanceConstraintFunc,AfterMemoryInit)\ 1309 \ 1310 product(intx, AllocatePrefetchLines, 3, \ 1311 "Number of lines to prefetch ahead of array allocation pointer") \ 1312 range(1, 64) \ 1313 \ 1314 product(intx, AllocateInstancePrefetchLines, 1, \ 1315 "Number of lines to prefetch ahead of instance allocation " \ 1316 "pointer") \ 1317 range(1, 64) \ 1318 \ 1319 product(intx, AllocatePrefetchStepSize, 16, \ 1320 "Step size in bytes of sequential prefetch instructions") \ 1321 range(1, 512) \ 1322 constraint(AllocatePrefetchStepSizeConstraintFunc,AfterMemoryInit)\ 1323 \ 1324 product(intx, AllocatePrefetchInstr, 0, \ 1325 "Select instruction to prefetch ahead of allocation pointer") \ 1326 constraint(AllocatePrefetchInstrConstraintFunc, AfterMemoryInit) \ 1327 \ 1328 /* deoptimization */ \ 1329 develop(bool, TraceDeoptimization, false, \ 1330 "Trace deoptimization") \ 1331 \ 1332 develop(bool, PrintDeoptimizationDetails, false, \ 1333 "Print more information about deoptimization") \ 1334 \ 1335 develop(bool, DebugDeoptimization, false, \ 1336 "Tracing various information while debugging deoptimization") \ 1337 \ 1338 product(intx, SelfDestructTimer, 0, \ 1339 "Will cause VM to terminate after a given time (in minutes) " \ 1340 "(0 means off)") \ 1341 range(0, max_intx) \ 1342 \ 1343 product(intx, MaxJavaStackTraceDepth, 1024, \ 1344 "The maximum number of lines in the stack trace for Java " \ 1345 "exceptions (0 means all)") \ 1346 range(0, max_jint/2) \ 1347 \ 1348 /* notice: the max range value here is max_jint, not max_intx */ \ 1349 /* because of overflow issue */ \ 1350 product(intx, GuaranteedSafepointInterval, 1000, DIAGNOSTIC, \ 1351 "Guarantee a safepoint (at least) every so many milliseconds " \ 1352 "(0 means none)") \ 1353 range(0, max_jint) \ 1354 \ 1355 product(intx, SafepointTimeoutDelay, 10000, \ 1356 "Delay in milliseconds for option SafepointTimeout") \ 1357 range(0, max_intx LP64_ONLY(/MICROUNITS)) \ 1358 \ 1359 product(intx, NmethodSweepActivity, 10, \ 1360 "Removes cold nmethods from code cache if > 0. Higher values " \ 1361 "result in more aggressive sweeping") \ 1362 range(0, 2000) \ 1363 \ 1364 notproduct(bool, LogSweeper, false, \ 1365 "Keep a ring buffer of sweeper activity") \ 1366 \ 1367 notproduct(intx, SweeperLogEntries, 1024, \ 1368 "Number of records in the ring buffer of sweeper activity") \ 1369 \ 1370 develop(intx, MallocCatchPtr, -1, \ 1371 "Hit breakpoint when mallocing/freeing this pointer") \ 1372 \ 1373 notproduct(ccstrlist, SuppressErrorAt, "", \ 1374 "List of assertions (file:line) to muzzle") \ 1375 \ 1376 develop(intx, StackPrintLimit, 100, \ 1377 "number of stack frames to print in VM-level stack dump") \ 1378 \ 1379 product(int, ErrorLogPrintCodeLimit, 3, DIAGNOSTIC, \ 1380 "max number of compiled code units to print in error log") \ 1381 range(0, VMError::max_error_log_print_code) \ 1382 \ 1383 notproduct(intx, MaxElementPrintSize, 256, \ 1384 "maximum number of elements to print") \ 1385 \ 1386 notproduct(intx, MaxSubklassPrintSize, 4, \ 1387 "maximum number of subklasses to print when printing klass") \ 1388 \ 1389 develop(intx, MaxForceInlineLevel, 100, \ 1390 "maximum number of nested calls that are forced for inlining " \ 1391 "(using CompileCommand or marked w/ @ForceInline)") \ 1392 range(0, max_jint) \ 1393 \ 1394 product(intx, MinInliningThreshold, 250, \ 1395 "The minimum invocation count a method needs to have to be " \ 1396 "inlined") \ 1397 range(0, max_jint) \ 1398 \ 1399 develop(intx, MethodHistogramCutoff, 100, \ 1400 "The cutoff value for method invocation histogram (+CountCalls)") \ 1401 \ 1402 develop(intx, DontYieldALotInterval, 10, \ 1403 "Interval between which yields will be dropped (milliseconds)") \ 1404 \ 1405 notproduct(intx, DeoptimizeALotInterval, 5, \ 1406 "Number of exits until DeoptimizeALot kicks in") \ 1407 \ 1408 notproduct(intx, ZombieALotInterval, 5, \ 1409 "Number of exits until ZombieALot kicks in") \ 1410 \ 1411 product(uintx, MallocMaxTestWords, 0, DIAGNOSTIC, \ 1412 "If non-zero, maximum number of words that malloc/realloc can " \ 1413 "allocate (for testing only)") \ 1414 range(0, max_uintx) \ 1415 \ 1416 product(intx, TypeProfileWidth, 2, \ 1417 "Number of receiver types to record in call/cast profile") \ 1418 range(0, 8) \ 1419 \ 1420 develop(intx, BciProfileWidth, 2, \ 1421 "Number of return bci's to record in ret profile") \ 1422 \ 1423 product(intx, PerMethodRecompilationCutoff, 400, \ 1424 "After recompiling N times, stay in the interpreter (-1=>'Inf')") \ 1425 range(-1, max_intx) \ 1426 \ 1427 product(intx, PerBytecodeRecompilationCutoff, 200, \ 1428 "Per-BCI limit on repeated recompilation (-1=>'Inf')") \ 1429 range(-1, max_intx) \ 1430 \ 1431 product(intx, PerMethodTrapLimit, 100, \ 1432 "Limit on traps (of one kind) in a method (includes inlines)") \ 1433 range(0, max_jint) \ 1434 \ 1435 product(intx, PerMethodSpecTrapLimit, 5000, EXPERIMENTAL, \ 1436 "Limit on speculative traps (of one kind) in a method " \ 1437 "(includes inlines)") \ 1438 range(0, max_jint) \ 1439 \ 1440 product(intx, PerBytecodeTrapLimit, 4, \ 1441 "Limit on traps (of one kind) at a particular BCI") \ 1442 range(0, max_jint) \ 1443 \ 1444 product(intx, SpecTrapLimitExtraEntries, 3, EXPERIMENTAL, \ 1445 "Extra method data trap entries for speculation") \ 1446 \ 1447 develop(intx, InlineFrequencyRatio, 20, \ 1448 "Ratio of call site execution to caller method invocation") \ 1449 range(0, max_jint) \ 1450 \ 1451 product_pd(intx, InlineFrequencyCount, DIAGNOSTIC, \ 1452 "Count of call site execution necessary to trigger frequent " \ 1453 "inlining") \ 1454 range(0, max_jint) \ 1455 \ 1456 develop(intx, InlineThrowCount, 50, \ 1457 "Force inlining of interpreted methods that throw this often") \ 1458 range(0, max_jint) \ 1459 \ 1460 develop(intx, InlineThrowMaxSize, 200, \ 1461 "Force inlining of throwing methods smaller than this") \ 1462 range(0, max_jint) \ 1463 \ 1464 product(size_t, MetaspaceSize, NOT_LP64(16 * M) LP64_ONLY(21 * M), \ 1465 "Initial threshold (in bytes) at which a garbage collection " \ 1466 "is done to reduce Metaspace usage") \ 1467 constraint(MetaspaceSizeConstraintFunc,AfterErgo) \ 1468 \ 1469 product(size_t, MaxMetaspaceSize, max_uintx, \ 1470 "Maximum size of Metaspaces (in bytes)") \ 1471 constraint(MaxMetaspaceSizeConstraintFunc,AfterErgo) \ 1472 \ 1473 product(size_t, CompressedClassSpaceSize, 1*G, \ 1474 "Maximum size of class area in Metaspace when compressed " \ 1475 "class pointers are used") \ 1476 range(1*M, 3*G) \ 1477 \ 1478 develop(size_t, CompressedClassSpaceBaseAddress, 0, \ 1479 "Force the class space to be allocated at this address or " \ 1480 "fails VM initialization (requires -Xshare=off.") \ 1481 \ 1482 product(ccstr, MetaspaceReclaimPolicy, "balanced", \ 1483 "options: balanced, aggressive, none") \ 1484 \ 1485 product(bool, PrintMetaspaceStatisticsAtExit, false, DIAGNOSTIC, \ 1486 "Print metaspace statistics upon VM exit.") \ 1487 \ 1488 product(bool, MetaspaceGuardAllocations, false, DIAGNOSTIC, \ 1489 "Metapace allocations are guarded.") \ 1490 \ 1491 product(bool, MetaspaceHandleDeallocations, true, DIAGNOSTIC, \ 1492 "Switch off Metapace deallocation handling.") \ 1493 \ 1494 product(uintx, MinHeapFreeRatio, 40, MANAGEABLE, \ 1495 "The minimum percentage of heap free after GC to avoid expansion."\ 1496 " For most GCs this applies to the old generation. In G1 and" \ 1497 " ParallelGC it applies to the whole heap.") \ 1498 range(0, 100) \ 1499 constraint(MinHeapFreeRatioConstraintFunc,AfterErgo) \ 1500 \ 1501 product(uintx, MaxHeapFreeRatio, 70, MANAGEABLE, \ 1502 "The maximum percentage of heap free after GC to avoid shrinking."\ 1503 " For most GCs this applies to the old generation. In G1 and" \ 1504 " ParallelGC it applies to the whole heap.") \ 1505 range(0, 100) \ 1506 constraint(MaxHeapFreeRatioConstraintFunc,AfterErgo) \ 1507 \ 1508 product(bool, ShrinkHeapInSteps, true, \ 1509 "When disabled, informs the GC to shrink the java heap directly" \ 1510 " to the target size at the next full GC rather than requiring" \ 1511 " smaller steps during multiple full GCs.") \ 1512 \ 1513 product(intx, SoftRefLRUPolicyMSPerMB, 1000, \ 1514 "Number of milliseconds per MB of free space in the heap") \ 1515 range(0, max_intx) \ 1516 constraint(SoftRefLRUPolicyMSPerMBConstraintFunc,AfterMemoryInit) \ 1517 \ 1518 product(size_t, MinHeapDeltaBytes, ScaleForWordSize(128*K), \ 1519 "The minimum change in heap space due to GC (in bytes)") \ 1520 range(0, max_uintx) \ 1521 \ 1522 product(size_t, MinMetaspaceExpansion, ScaleForWordSize(256*K), \ 1523 "The minimum expansion of Metaspace (in bytes)") \ 1524 range(0, max_uintx) \ 1525 \ 1526 product(uintx, MaxMetaspaceFreeRatio, 70, \ 1527 "The maximum percentage of Metaspace free after GC to avoid " \ 1528 "shrinking") \ 1529 range(0, 100) \ 1530 constraint(MaxMetaspaceFreeRatioConstraintFunc,AfterErgo) \ 1531 \ 1532 product(uintx, MinMetaspaceFreeRatio, 40, \ 1533 "The minimum percentage of Metaspace free after GC to avoid " \ 1534 "expansion") \ 1535 range(0, 99) \ 1536 constraint(MinMetaspaceFreeRatioConstraintFunc,AfterErgo) \ 1537 \ 1538 product(size_t, MaxMetaspaceExpansion, ScaleForWordSize(4*M), \ 1539 "The maximum expansion of Metaspace without full GC (in bytes)") \ 1540 range(0, max_uintx) \ 1541 \ 1542 /* stack parameters */ \ 1543 product_pd(intx, StackYellowPages, \ 1544 "Number of yellow zone (recoverable overflows) pages of size " \ 1545 "4KB. If pages are bigger yellow zone is aligned up.") \ 1546 range(MIN_STACK_YELLOW_PAGES, (DEFAULT_STACK_YELLOW_PAGES+5)) \ 1547 \ 1548 product_pd(intx, StackRedPages, \ 1549 "Number of red zone (unrecoverable overflows) pages of size " \ 1550 "4KB. If pages are bigger red zone is aligned up.") \ 1551 range(MIN_STACK_RED_PAGES, (DEFAULT_STACK_RED_PAGES+2)) \ 1552 \ 1553 product_pd(intx, StackReservedPages, \ 1554 "Number of reserved zone (reserved to annotated methods) pages" \ 1555 " of size 4KB. If pages are bigger reserved zone is aligned up.") \ 1556 range(MIN_STACK_RESERVED_PAGES, (DEFAULT_STACK_RESERVED_PAGES+10))\ 1557 \ 1558 product(bool, RestrictReservedStack, true, \ 1559 "Restrict @ReservedStackAccess to trusted classes") \ 1560 \ 1561 /* greater stack shadow pages can't generate instruction to bang stack */ \ 1562 product_pd(intx, StackShadowPages, \ 1563 "Number of shadow zone (for overflow checking) pages of size " \ 1564 "4KB. If pages are bigger shadow zone is aligned up. " \ 1565 "This should exceed the depth of the VM and native call stack.") \ 1566 range(MIN_STACK_SHADOW_PAGES, (DEFAULT_STACK_SHADOW_PAGES+30)) \ 1567 \ 1568 product_pd(intx, ThreadStackSize, \ 1569 "Thread Stack Size (in Kbytes)") \ 1570 range(0, 1 * M) \ 1571 \ 1572 product_pd(intx, VMThreadStackSize, \ 1573 "Non-Java Thread Stack Size (in Kbytes)") \ 1574 range(0, max_intx/(1 * K)) \ 1575 \ 1576 product_pd(intx, CompilerThreadStackSize, \ 1577 "Compiler Thread Stack Size (in Kbytes)") \ 1578 range(0, max_intx/(1 * K)) \ 1579 \ 1580 develop_pd(size_t, JVMInvokeMethodSlack, \ 1581 "Stack space (bytes) required for JVM_InvokeMethod to complete") \ 1582 \ 1583 /* code cache parameters */ \ 1584 product_pd(uintx, CodeCacheSegmentSize, EXPERIMENTAL, \ 1585 "Code cache segment size (in bytes) - smallest unit of " \ 1586 "allocation") \ 1587 range(1, 1024) \ 1588 constraint(CodeCacheSegmentSizeConstraintFunc, AfterErgo) \ 1589 \ 1590 develop_pd(intx, CodeEntryAlignment, \ 1591 "Code entry alignment for generated code (in bytes)") \ 1592 constraint(CodeEntryAlignmentConstraintFunc, AfterErgo) \ 1593 \ 1594 product_pd(intx, OptoLoopAlignment, \ 1595 "Align inner loops to zero relative to this modulus") \ 1596 range(1, 16) \ 1597 constraint(OptoLoopAlignmentConstraintFunc, AfterErgo) \ 1598 \ 1599 product_pd(uintx, InitialCodeCacheSize, \ 1600 "Initial code cache size (in bytes)") \ 1601 constraint(VMPageSizeConstraintFunc, AtParse) \ 1602 \ 1603 develop_pd(uintx, CodeCacheMinimumUseSpace, \ 1604 "Minimum code cache size (in bytes) required to start VM.") \ 1605 range(0, max_uintx) \ 1606 \ 1607 product(bool, SegmentedCodeCache, false, \ 1608 "Use a segmented code cache") \ 1609 \ 1610 product_pd(uintx, ReservedCodeCacheSize, \ 1611 "Reserved code cache size (in bytes) - maximum code cache size") \ 1612 constraint(VMPageSizeConstraintFunc, AtParse) \ 1613 \ 1614 product_pd(uintx, NonProfiledCodeHeapSize, \ 1615 "Size of code heap with non-profiled methods (in bytes)") \ 1616 range(0, max_uintx) \ 1617 \ 1618 product_pd(uintx, ProfiledCodeHeapSize, \ 1619 "Size of code heap with profiled methods (in bytes)") \ 1620 range(0, max_uintx) \ 1621 \ 1622 product_pd(uintx, NonNMethodCodeHeapSize, \ 1623 "Size of code heap with non-nmethods (in bytes)") \ 1624 constraint(VMPageSizeConstraintFunc, AtParse) \ 1625 \ 1626 product_pd(uintx, CodeCacheExpansionSize, \ 1627 "Code cache expansion size (in bytes)") \ 1628 range(32*K, max_uintx) \ 1629 \ 1630 product_pd(uintx, CodeCacheMinBlockLength, DIAGNOSTIC, \ 1631 "Minimum number of segments in a code cache block") \ 1632 range(1, 100) \ 1633 \ 1634 notproduct(bool, ExitOnFullCodeCache, false, \ 1635 "Exit the VM if we fill the code cache") \ 1636 \ 1637 product(bool, UseCodeCacheFlushing, true, \ 1638 "Remove cold/old nmethods from the code cache") \ 1639 \ 1640 product(double, SweeperThreshold, 0.5, \ 1641 "Threshold controlling when code cache sweeper is invoked." \ 1642 "Value is percentage of ReservedCodeCacheSize.") \ 1643 range(0.0, 100.0) \ 1644 \ 1645 product(uintx, StartAggressiveSweepingAt, 10, \ 1646 "Start aggressive sweeping if X[%] of the code cache is free." \ 1647 "Segmented code cache: X[%] of the non-profiled heap." \ 1648 "Non-segmented code cache: X[%] of the total code cache") \ 1649 range(0, 100) \ 1650 \ 1651 /* interpreter debugging */ \ 1652 develop(intx, BinarySwitchThreshold, 5, \ 1653 "Minimal number of lookupswitch entries for rewriting to binary " \ 1654 "switch") \ 1655 \ 1656 develop(intx, StopInterpreterAt, 0, \ 1657 "Stop interpreter execution at specified bytecode number") \ 1658 \ 1659 develop(intx, TraceBytecodesAt, 0, \ 1660 "Trace bytecodes starting with specified bytecode number") \ 1661 \ 1662 /* Priorities */ \ 1663 product_pd(bool, UseThreadPriorities, "Use native thread priorities") \ 1664 \ 1665 product(intx, ThreadPriorityPolicy, 0, \ 1666 "0 : Normal. "\ 1667 " VM chooses priorities that are appropriate for normal "\ 1668 " applications. "\ 1669 " On Windows applications are allowed to use higher native "\ 1670 " priorities. However, with ThreadPriorityPolicy=0, VM will "\ 1671 " not use the highest possible native priority, "\ 1672 " THREAD_PRIORITY_TIME_CRITICAL, as it may interfere with "\ 1673 " system threads. On Linux thread priorities are ignored "\ 1674 " because the OS does not support static priority in "\ 1675 " SCHED_OTHER scheduling class which is the only choice for "\ 1676 " non-root, non-realtime applications. "\ 1677 "1 : Aggressive. "\ 1678 " Java thread priorities map over to the entire range of "\ 1679 " native thread priorities. Higher Java thread priorities map "\ 1680 " to higher native thread priorities. This policy should be "\ 1681 " used with care, as sometimes it can cause performance "\ 1682 " degradation in the application and/or the entire system. On "\ 1683 " Linux/BSD/macOS this policy requires root privilege or an "\ 1684 " extended capability.") \ 1685 range(0, 1) \ 1686 \ 1687 product(bool, ThreadPriorityVerbose, false, \ 1688 "Print priority changes") \ 1689 \ 1690 product(intx, CompilerThreadPriority, -1, \ 1691 "The native priority at which compiler threads should run " \ 1692 "(-1 means no change)") \ 1693 range(min_jint, max_jint) \ 1694 \ 1695 product(intx, VMThreadPriority, -1, \ 1696 "The native priority at which the VM thread should run " \ 1697 "(-1 means no change)") \ 1698 range(-1, 127) \ 1699 \ 1700 product(intx, JavaPriority1_To_OSPriority, -1, \ 1701 "Map Java priorities to OS priorities") \ 1702 range(-1, 127) \ 1703 \ 1704 product(intx, JavaPriority2_To_OSPriority, -1, \ 1705 "Map Java priorities to OS priorities") \ 1706 range(-1, 127) \ 1707 \ 1708 product(intx, JavaPriority3_To_OSPriority, -1, \ 1709 "Map Java priorities to OS priorities") \ 1710 range(-1, 127) \ 1711 \ 1712 product(intx, JavaPriority4_To_OSPriority, -1, \ 1713 "Map Java priorities to OS priorities") \ 1714 range(-1, 127) \ 1715 \ 1716 product(intx, JavaPriority5_To_OSPriority, -1, \ 1717 "Map Java priorities to OS priorities") \ 1718 range(-1, 127) \ 1719 \ 1720 product(intx, JavaPriority6_To_OSPriority, -1, \ 1721 "Map Java priorities to OS priorities") \ 1722 range(-1, 127) \ 1723 \ 1724 product(intx, JavaPriority7_To_OSPriority, -1, \ 1725 "Map Java priorities to OS priorities") \ 1726 range(-1, 127) \ 1727 \ 1728 product(intx, JavaPriority8_To_OSPriority, -1, \ 1729 "Map Java priorities to OS priorities") \ 1730 range(-1, 127) \ 1731 \ 1732 product(intx, JavaPriority9_To_OSPriority, -1, \ 1733 "Map Java priorities to OS priorities") \ 1734 range(-1, 127) \ 1735 \ 1736 product(intx, JavaPriority10_To_OSPriority,-1, \ 1737 "Map Java priorities to OS priorities") \ 1738 range(-1, 127) \ 1739 \ 1740 product(bool, UseCriticalJavaThreadPriority, false, EXPERIMENTAL, \ 1741 "Java thread priority 10 maps to critical scheduling priority") \ 1742 \ 1743 product(bool, UseCriticalCompilerThreadPriority, false, EXPERIMENTAL, \ 1744 "Compiler thread(s) run at critical scheduling priority") \ 1745 \ 1746 develop(intx, NewCodeParameter, 0, \ 1747 "Testing Only: Create a dedicated integer parameter before " \ 1748 "putback") \ 1749 \ 1750 /* new oopmap storage allocation */ \ 1751 develop(intx, MinOopMapAllocation, 8, \ 1752 "Minimum number of OopMap entries in an OopMapSet") \ 1753 \ 1754 /* recompilation */ \ 1755 product_pd(intx, CompileThreshold, \ 1756 "number of interpreted method invocations before (re-)compiling") \ 1757 constraint(CompileThresholdConstraintFunc, AfterErgo) \ 1758 \ 1759 product_pd(bool, TieredCompilation, \ 1760 "Enable tiered compilation") \ 1761 \ 1762 /* Properties for Java libraries */ \ 1763 \ 1764 product(uint64_t, MaxDirectMemorySize, 0, \ 1765 "Maximum total size of NIO direct-buffer allocations") \ 1766 range(0, max_jlong) \ 1767 \ 1768 /* Flags used for temporary code during development */ \ 1769 \ 1770 product(bool, UseNewCode, false, DIAGNOSTIC, \ 1771 "Testing Only: Use the new version while testing") \ 1772 \ 1773 product(bool, UseNewCode2, false, DIAGNOSTIC, \ 1774 "Testing Only: Use the new version while testing") \ 1775 \ 1776 product(bool, UseNewCode3, false, DIAGNOSTIC, \ 1777 "Testing Only: Use the new version while testing") \ 1778 \ 1779 notproduct(bool, UseDebuggerErgo, false, \ 1780 "Debugging Only: Adjust the VM to be more debugger-friendly. " \ 1781 "Turns on the other UseDebuggerErgo* flags") \ 1782 \ 1783 notproduct(bool, UseDebuggerErgo1, false, \ 1784 "Debugging Only: Enable workarounds for debugger induced " \ 1785 "os::processor_id() >= os::processor_count() problems") \ 1786 \ 1787 notproduct(bool, UseDebuggerErgo2, false, \ 1788 "Debugging Only: Limit the number of spawned JVM threads") \ 1789 \ 1790 notproduct(bool, EnableJVMTIStackDepthAsserts, true, \ 1791 "Enable JVMTI asserts related to stack depth checks") \ 1792 \ 1793 /* flags for performance data collection */ \ 1794 \ 1795 product(bool, UsePerfData, true, \ 1796 "Flag to disable jvmstat instrumentation for performance testing "\ 1797 "and problem isolation purposes") \ 1798 \ 1799 product(bool, PerfDataSaveToFile, false, \ 1800 "Save PerfData memory to hsperfdata_<pid> file on exit") \ 1801 \ 1802 product(ccstr, PerfDataSaveFile, NULL, \ 1803 "Save PerfData memory to the specified absolute pathname. " \ 1804 "The string %p in the file name (if present) " \ 1805 "will be replaced by pid") \ 1806 \ 1807 product(intx, PerfDataSamplingInterval, 50, \ 1808 "Data sampling interval (in milliseconds)") \ 1809 range(PeriodicTask::min_interval, max_jint) \ 1810 constraint(PerfDataSamplingIntervalFunc, AfterErgo) \ 1811 \ 1812 product(bool, PerfDisableSharedMem, false, \ 1813 "Store performance data in standard memory") \ 1814 \ 1815 product(intx, PerfDataMemorySize, 32*K, \ 1816 "Size of performance data memory region. Will be rounded " \ 1817 "up to a multiple of the native os page size.") \ 1818 range(128, 32*64*K) \ 1819 \ 1820 product(intx, PerfMaxStringConstLength, 1024, \ 1821 "Maximum PerfStringConstant string length before truncation") \ 1822 range(32, 32*K) \ 1823 \ 1824 product(bool, PerfAllowAtExitRegistration, false, \ 1825 "Allow registration of atexit() methods") \ 1826 \ 1827 product(bool, PerfBypassFileSystemCheck, false, \ 1828 "Bypass Win32 file system criteria checks (Windows Only)") \ 1829 \ 1830 product(intx, UnguardOnExecutionViolation, 0, \ 1831 "Unguard page and retry on no-execute fault (Win32 only) " \ 1832 "0=off, 1=conservative, 2=aggressive") \ 1833 range(0, 2) \ 1834 \ 1835 /* Serviceability Support */ \ 1836 \ 1837 product(bool, ManagementServer, false, \ 1838 "Create JMX Management Server") \ 1839 \ 1840 product(bool, DisableAttachMechanism, false, \ 1841 "Disable mechanism that allows tools to attach to this VM") \ 1842 \ 1843 product(bool, StartAttachListener, false, \ 1844 "Always start Attach Listener at VM startup") \ 1845 \ 1846 product(bool, EnableDynamicAgentLoading, true, \ 1847 "Allow tools to load agents with the attach mechanism") \ 1848 \ 1849 product(bool, PrintConcurrentLocks, false, MANAGEABLE, \ 1850 "Print java.util.concurrent locks in thread dump") \ 1851 \ 1852 /* Shared spaces */ \ 1853 \ 1854 product(bool, UseSharedSpaces, true, \ 1855 "Use shared spaces for metadata") \ 1856 \ 1857 product(bool, VerifySharedSpaces, false, \ 1858 "Verify integrity of shared spaces") \ 1859 \ 1860 product(bool, RequireSharedSpaces, false, \ 1861 "Require shared spaces for metadata") \ 1862 \ 1863 product(bool, DumpSharedSpaces, false, \ 1864 "Special mode: JVM reads a class list, loads classes, builds " \ 1865 "shared spaces, and dumps the shared spaces to a file to be " \ 1866 "used in future JVM runs") \ 1867 \ 1868 product(bool, DynamicDumpSharedSpaces, false, \ 1869 "Dynamic archive") \ 1870 \ 1871 product(bool, RecordDynamicDumpInfo, false, \ 1872 "Record class info for jcmd VM.cds dynamic_dump") \ 1873 \ 1874 product(bool, PrintSharedArchiveAndExit, false, \ 1875 "Print shared archive file contents") \ 1876 \ 1877 product(bool, PrintSharedDictionary, false, \ 1878 "If PrintSharedArchiveAndExit is true, also print the shared " \ 1879 "dictionary") \ 1880 \ 1881 product(size_t, SharedBaseAddress, LP64_ONLY(32*G) \ 1882 NOT_LP64(LINUX_ONLY(2*G) NOT_LINUX(0)), \ 1883 "Address to allocate shared memory region for class data") \ 1884 range(0, SIZE_MAX) \ 1885 \ 1886 product(ccstr, SharedArchiveConfigFile, NULL, \ 1887 "Data to add to the CDS archive file") \ 1888 \ 1889 product(uintx, SharedSymbolTableBucketSize, 4, \ 1890 "Average number of symbols per bucket in shared table") \ 1891 range(2, 246) \ 1892 \ 1893 product(bool, AllowArchivingWithJavaAgent, false, DIAGNOSTIC, \ 1894 "Allow Java agent to be run with CDS dumping") \ 1895 \ 1896 product(bool, PrintMethodHandleStubs, false, DIAGNOSTIC, \ 1897 "Print generated stub code for method handles") \ 1898 \ 1899 product(bool, VerifyMethodHandles, trueInDebug, DIAGNOSTIC, \ 1900 "perform extra checks when constructing method handles") \ 1901 \ 1902 product(bool, ShowHiddenFrames, false, DIAGNOSTIC, \ 1903 "show method handle implementation frames (usually hidden)") \ 1904 \ 1905 product(bool, TrustFinalNonStaticFields, false, EXPERIMENTAL, \ 1906 "trust final non-static declarations for constant folding") \ 1907 \ 1908 product(bool, FoldStableValues, true, DIAGNOSTIC, \ 1909 "Optimize loads from stable fields (marked w/ @Stable)") \ 1910 \ 1911 product(int, UseBootstrapCallInfo, 1, DIAGNOSTIC, \ 1912 "0: when resolving InDy or ConDy, force all BSM arguments to be " \ 1913 "resolved before the bootstrap method is called; 1: when a BSM " \ 1914 "that may accept a BootstrapCallInfo is detected, use that API " \ 1915 "to pass BSM arguments, which allows the BSM to delay their " \ 1916 "resolution; 2+: stress test the BCI API by calling more BSMs " \ 1917 "via that API, instead of with the eagerly-resolved array.") \ 1918 \ 1919 product(bool, PauseAtStartup, false, DIAGNOSTIC, \ 1920 "Causes the VM to pause at startup time and wait for the pause " \ 1921 "file to be removed (default: ./vm.paused.<pid>)") \ 1922 \ 1923 product(ccstr, PauseAtStartupFile, NULL, DIAGNOSTIC, \ 1924 "The file to create and for whose removal to await when pausing " \ 1925 "at startup. (default: ./vm.paused.<pid>)") \ 1926 \ 1927 product(bool, PauseAtExit, false, DIAGNOSTIC, \ 1928 "Pause and wait for keypress on exit if a debugger is attached") \ 1929 \ 1930 product(bool, ExtendedDTraceProbes, false, \ 1931 "Enable performance-impacting dtrace probes") \ 1932 \ 1933 product(bool, DTraceMethodProbes, false, \ 1934 "Enable dtrace probes for method-entry and method-exit") \ 1935 \ 1936 product(bool, DTraceAllocProbes, false, \ 1937 "Enable dtrace probes for object allocation") \ 1938 \ 1939 product(bool, DTraceMonitorProbes, false, \ 1940 "Enable dtrace probes for monitor events") \ 1941 \ 1942 product(bool, RelaxAccessControlCheck, false, \ 1943 "Relax the access control checks in the verifier") \ 1944 \ 1945 product(uintx, StringTableSize, defaultStringTableSize, \ 1946 "Number of buckets in the interned String table " \ 1947 "(will be rounded to nearest higher power of 2)") \ 1948 range(minimumStringTableSize, 16777216ul /* 2^24 */) \ 1949 \ 1950 product(uintx, SymbolTableSize, defaultSymbolTableSize, EXPERIMENTAL, \ 1951 "Number of buckets in the JVM internal Symbol table") \ 1952 range(minimumSymbolTableSize, 16777216ul /* 2^24 */) \ 1953 \ 1954 product(bool, UseStringDeduplication, false, \ 1955 "Use string deduplication") \ 1956 \ 1957 product(uint, StringDeduplicationAgeThreshold, 3, \ 1958 "A string must reach this age (or be promoted to an old region) " \ 1959 "to be considered for deduplication") \ 1960 range(1, markWord::max_age) \ 1961 \ 1962 product(size_t, StringDeduplicationInitialTableSize, 500, EXPERIMENTAL, \ 1963 "Approximate initial number of buckets in the table") \ 1964 range(1, 1 * G) \ 1965 \ 1966 product(double, StringDeduplicationGrowTableLoad, 14.0, EXPERIMENTAL, \ 1967 "Entries per bucket above which the table should be expanded") \ 1968 range(0.1, 1000.0) \ 1969 \ 1970 product(double, StringDeduplicationShrinkTableLoad, 1.0, EXPERIMENTAL, \ 1971 "Entries per bucket below which the table should be shrunk") \ 1972 range(0.01, 100.0) \ 1973 \ 1974 product(double, StringDeduplicationTargetTableLoad, 7.0, EXPERIMENTAL, \ 1975 "Desired entries per bucket when resizing the table") \ 1976 range(0.01, 1000.0) \ 1977 \ 1978 product(size_t, StringDeduplicationCleanupDeadMinimum, 100, EXPERIMENTAL, \ 1979 "Minimum number of dead table entries for cleaning the table") \ 1980 \ 1981 product(int, StringDeduplicationCleanupDeadPercent, 5, EXPERIMENTAL, \ 1982 "Minimum percentage of dead table entries for cleaning the table") \ 1983 range(1, 100) \ 1984 \ 1985 product(bool, StringDeduplicationResizeALot, false, DIAGNOSTIC, \ 1986 "Force more frequent table resizing") \ 1987 \ 1988 product(uint64_t, StringDeduplicationHashSeed, 0, DIAGNOSTIC, \ 1989 "Seed for the table hashing function; 0 requests computed seed") \ 1990 \ 1991 product(bool, WhiteBoxAPI, false, DIAGNOSTIC, \ 1992 "Enable internal testing APIs") \ 1993 \ 1994 product(ccstr, DumpLoadedClassList, NULL, \ 1995 "Dump the names all loaded classes, that could be stored into " \ 1996 "the CDS archive, in the specified file") \ 1997 \ 1998 product(ccstr, SharedClassListFile, NULL, \ 1999 "Override the default CDS class list") \ 2000 \ 2001 product(ccstr, SharedArchiveFile, NULL, \ 2002 "Override the default location of the CDS archive file") \ 2003 \ 2004 product(ccstr, ArchiveClassesAtExit, NULL, \ 2005 "The path and name of the dynamic archive file") \ 2006 \ 2007 product(ccstr, ExtraSharedClassListFile, NULL, \ 2008 "Extra classlist for building the CDS archive file") \ 2009 \ 2010 product(intx, ArchiveRelocationMode, 1, DIAGNOSTIC, \ 2011 "(0) first map at preferred address, and if " \ 2012 "unsuccessful, map at alternative address; " \ 2013 "(1) always map at alternative address (default); " \ 2014 "(2) always map at preferred address, and if unsuccessful, " \ 2015 "do not map the archive") \ 2016 range(0, 2) \ 2017 \ 2018 product(size_t, ArrayAllocatorMallocLimit, (size_t)-1, EXPERIMENTAL, \ 2019 "Allocation less than this value will be allocated " \ 2020 "using malloc. Larger allocations will use mmap.") \ 2021 \ 2022 product(bool, AlwaysAtomicAccesses, false, EXPERIMENTAL, \ 2023 "Accesses to all variables should always be atomic") \ 2024 \ 2025 product(bool, UseUnalignedAccesses, false, DIAGNOSTIC, \ 2026 "Use unaligned memory accesses in Unsafe") \ 2027 \ 2028 product_pd(bool, PreserveFramePointer, \ 2029 "Use the FP register for holding the frame pointer " \ 2030 "and not as a general purpose register.") \ 2031 \ 2032 product(size_t, AsyncLogBufferSize, 2*M, \ 2033 "Memory budget (in bytes) for the buffer of Asynchronous " \ 2034 "Logging (-Xlog:async).") \ 2035 range(100*K, 50*M) \ 2036 \ 2037 product(bool, CheckIntrinsics, true, DIAGNOSTIC, \ 2038 "When a class C is loaded, check that " \ 2039 "(1) all intrinsics defined by the VM for class C are present "\ 2040 "in the loaded class file and are marked with the " \ 2041 "@IntrinsicCandidate annotation, that " \ 2042 "(2) there is an intrinsic registered for all loaded methods " \ 2043 "that are annotated with the @IntrinsicCandidate annotation, " \ 2044 "and that " \ 2045 "(3) no orphan methods exist for class C (i.e., methods for " \ 2046 "which the VM declares an intrinsic but that are not declared "\ 2047 "in the loaded class C. " \ 2048 "Check (3) is available only in debug builds.") \ 2049 \ 2050 product_pd(intx, InitArrayShortSize, DIAGNOSTIC, \ 2051 "Threshold small size (in bytes) for clearing arrays. " \ 2052 "Anything this size or smaller may get converted to discrete " \ 2053 "scalar stores.") \ 2054 range(0, max_intx) \ 2055 constraint(InitArrayShortSizeConstraintFunc, AfterErgo) \ 2056 \ 2057 product(ccstr, AllocateHeapAt, NULL, \ 2058 "Path to the directory where a temporary file will be created " \ 2059 "to use as the backing store for Java Heap.") \ 2060 \ 2061 develop(int, VerifyMetaspaceInterval, DEBUG_ONLY(500) NOT_DEBUG(0), \ 2062 "Run periodic metaspace verifications (0 - none, " \ 2063 "1 - always, >1 every nth interval)") \ 2064 \ 2065 product(bool, ShowRegistersOnAssert, true, DIAGNOSTIC, \ 2066 "On internal errors, include registers in error report.") \ 2067 \ 2068 product(bool, UseSwitchProfiling, true, DIAGNOSTIC, \ 2069 "leverage profiling for table/lookup switch") \ 2070 \ 2071 develop(bool, TraceMemoryWriteback, false, \ 2072 "Trace memory writeback operations") \ 2073 \ 2074 JFR_ONLY(product(bool, FlightRecorder, false, \ 2075 "(Deprecated) Enable Flight Recorder")) \ 2076 \ 2077 JFR_ONLY(product(ccstr, FlightRecorderOptions, NULL, \ 2078 "Flight Recorder options")) \ 2079 \ 2080 JFR_ONLY(product(ccstr, StartFlightRecording, NULL, \ 2081 "Start flight recording with options")) \ 2082 \ 2083 product(bool, UseFastUnorderedTimeStamps, false, EXPERIMENTAL, \ 2084 "Use platform unstable time where supported for timestamps only") \ 2085 \ 2086 product(bool, UseEmptySlotsInSupers, true, \ 2087 "Allow allocating fields in empty slots of super-classes") \ 2088 \ 2089 product(bool, DeoptimizeNMethodBarriersALot, false, DIAGNOSTIC, \ 2090 "Make nmethod barriers deoptimise a lot.") \ 2091 \ 2092 develop(bool, VerifyCrossModifyFence, \ 2093 false AARCH64_ONLY(DEBUG_ONLY(||true)), \ 2094 "Mark all threads after a safepoint, and clear on a modify " \ 2095 "fence. Add cleanliness checks.") \ 2096 \ 2097 develop(bool, TraceOptimizedUpcallStubs, false, \ 2098 "Trace optimized upcall stub generation") \ 2099 \ 2100 product(uint, TrimNativeHeapInterval, 0, EXPERIMENTAL, \ 2101 "Interval, in ms, at which the JVM will trim the native heap if " \ 2102 "the platform supports that. Lower values will reclaim memory " \ 2103 "more eagerly at the cost of higher overhead. A value of 0 " \ 2104 "(default) disables native heap trimming.") \ 2105 range(0, UINT_MAX) \ 2106 2107 // end of RUNTIME_FLAGS 2108 2109 DECLARE_FLAGS(LP64_RUNTIME_FLAGS) 2110 DECLARE_ARCH_FLAGS(ARCH_FLAGS) 2111 DECLARE_FLAGS(RUNTIME_FLAGS) 2112 DECLARE_FLAGS(RUNTIME_OS_FLAGS) 2113 2114 #endif // SHARE_RUNTIME_GLOBALS_HPP