1 /* 2 * Copyright (c) 1997, 2024, 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 // develop_pd/product_pd flags are the same as develop/product, except that their default values 40 // are specified in platform-dependent header files. 41 42 // Flags must be declared with the following number of parameters: 43 // non-pd flags: 44 // (type, name, default_value, doc), or 45 // (type, name, default_value, extra_attrs, doc) 46 // pd flags: 47 // (type, name, doc), or 48 // (type, name, extra_attrs, doc) 49 50 // A flag must be declared with one of the following types: 51 // bool, int, uint, intx, uintx, size_t, ccstr, ccstrlist, double, or uint64_t. 52 // The type "ccstr" and "ccstrlist" are an alias for "const char*" and is used 53 // only in this file, because the macrology requires single-token type names. 54 55 // The optional extra_attrs parameter may have one of the following values: 56 // DIAGNOSTIC, EXPERIMENTAL, or MANAGEABLE. Currently extra_attrs can be used 57 // only with product/product_pd flags. 58 // 59 // DIAGNOSTIC options are not meant for VM tuning or for product modes. 60 // They are to be used for VM quality assurance or field diagnosis 61 // of VM bugs. They are hidden so that users will not be encouraged to 62 // try them as if they were VM ordinary execution options. However, they 63 // are available in the product version of the VM. Under instruction 64 // from support engineers, VM customers can turn them on to collect 65 // diagnostic information about VM problems. To use a VM diagnostic 66 // option, you must first specify +UnlockDiagnosticVMOptions. 67 // (This master switch also affects the behavior of -Xprintflags.) 68 // 69 // EXPERIMENTAL flags are in support of features that may not be 70 // an officially supported part of a product, but may be available 71 // for experimenting with. They could, for example, be performance 72 // features that may not have undergone full or rigorous QA, but which may 73 // help performance in some cases and released for experimentation 74 // by the community of users and developers. This flag also allows one to 75 // be able to build a fully supported product that nonetheless also 76 // ships with some unsupported, lightly tested, experimental features. 77 // Refer to the documentation of any products using this code for details 78 // on support and fitness for production. 79 // Like the UnlockDiagnosticVMOptions flag above, there is a corresponding 80 // UnlockExperimentalVMOptions flag, which allows the control and 81 // modification of the experimental flags. 82 // 83 // Nota bene: neither diagnostic nor experimental options should be used casually, 84 // Refer to the documentation of any products using this code for details. 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 CSR). 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 CSR request 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 range, \ 121 constraint) \ 122 \ 123 product(bool, UseCompressedOops, false, \ 124 "Use 32-bit object references in 64-bit VM. " \ 125 "lp64_product means flag is always constant in 32 bit VM") \ 126 \ 127 product(bool, UseCompressedClassPointers, true, \ 128 "Use 32-bit class pointers in 64-bit VM. " \ 129 "lp64_product means flag is always constant in 32 bit VM") \ 130 \ 131 product(bool, UseCompactObjectHeaders, false, EXPERIMENTAL, \ 132 "Use compact 64-bit object headers in 64-bit VM") \ 133 \ 134 product(int, ObjectAlignmentInBytes, 8, \ 135 "Default object alignment in bytes, 8 is minimum") \ 136 range(8, 256) \ 137 constraint(ObjectAlignmentInBytesConstraintFunc, AtParse) 138 139 #else 140 // !_LP64 141 142 #define LP64_RUNTIME_FLAGS(develop, \ 143 develop_pd, \ 144 product, \ 145 product_pd, \ 146 range, \ 147 constraint) 148 const bool UseCompressedOops = false; 149 const bool UseCompressedClassPointers = false; 150 const bool UseCompactObjectHeaders = false; 151 const int ObjectAlignmentInBytes = 8; 152 153 #endif // _LP64 154 155 #define RUNTIME_FLAGS(develop, \ 156 develop_pd, \ 157 product, \ 158 product_pd, \ 159 range, \ 160 constraint) \ 161 \ 162 develop(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(bool, UseAES, false, \ 224 "Control whether AES instructions are used when available") \ 225 \ 226 product(bool, UseFMA, false, \ 227 "Control whether FMA instructions are used when available") \ 228 \ 229 product(bool, UseSHA, false, \ 230 "Control whether SHA instructions are used when available") \ 231 \ 232 product(bool, UseGHASHIntrinsics, false, DIAGNOSTIC, \ 233 "Use intrinsics for GHASH versions of crypto") \ 234 \ 235 product(bool, UseBASE64Intrinsics, false, \ 236 "Use intrinsics for java.util.Base64") \ 237 \ 238 product(bool, UsePoly1305Intrinsics, false, DIAGNOSTIC, \ 239 "Use intrinsics for sun.security.util.math.intpoly") \ 240 product(bool, UseIntPolyIntrinsics, false, DIAGNOSTIC, \ 241 "Use intrinsics for sun.security.util.math.intpoly.MontgomeryIntegerPolynomialP256") \ 242 \ 243 product(size_t, LargePageSizeInBytes, 0, \ 244 "Maximum large page size used (0 will use the default large " \ 245 "page size for the environment as the maximum)") \ 246 range(0, max_uintx) \ 247 \ 248 product(size_t, LargePageHeapSizeThreshold, 128*M, \ 249 "Use large pages if maximum heap is at least this big") \ 250 range(0, max_uintx) \ 251 \ 252 product(bool, ForceTimeHighResolution, false, \ 253 "Using high time resolution (for Win32 only)") \ 254 \ 255 develop(bool, TracePcPatching, false, \ 256 "Trace usage of frame::patch_pc") \ 257 \ 258 develop(bool, TraceRelocator, false, \ 259 "Trace the bytecode relocator") \ 260 \ 261 \ 262 product(bool, SafepointALot, false, DIAGNOSTIC, \ 263 "Generate a lot of safepoints. This works with " \ 264 "GuaranteedSafepointInterval") \ 265 \ 266 product(bool, HandshakeALot, false, DIAGNOSTIC, \ 267 "Generate a lot of handshakes. This works with " \ 268 "GuaranteedSafepointInterval") \ 269 \ 270 product_pd(bool, BackgroundCompilation, \ 271 "A thread requesting compilation is not blocked during " \ 272 "compilation") \ 273 \ 274 product(bool, MethodFlushing, true, \ 275 "Reclamation of compiled methods") \ 276 \ 277 develop(bool, VerifyStack, false, \ 278 "Verify stack of each thread when it is entering a runtime call") \ 279 \ 280 product(bool, ForceUnreachable, false, DIAGNOSTIC, \ 281 "Make all non code cache addresses to be unreachable by " \ 282 "forcing use of 64bit literal fixups") \ 283 \ 284 develop(bool, TraceDerivedPointers, false, \ 285 "Trace traversal of derived pointers on stack") \ 286 \ 287 develop(bool, TraceCodeBlobStacks, false, \ 288 "Trace stack-walk of codeblobs") \ 289 \ 290 develop(bool, PrintRewrites, false, \ 291 "Print methods that are being rewritten") \ 292 \ 293 product(bool, UseInlineCaches, true, \ 294 "Use Inline Caches for virtual calls ") \ 295 \ 296 product(size_t, InlineCacheBufferSize, 10*K, EXPERIMENTAL, \ 297 "InlineCacheBuffer size") \ 298 \ 299 product(bool, InlineArrayCopy, true, DIAGNOSTIC, \ 300 "Inline arraycopy native that is known to be part of " \ 301 "base library DLL") \ 302 \ 303 product(bool, InlineObjectHash, true, DIAGNOSTIC, \ 304 "Inline Object::hashCode() native that is known to be part " \ 305 "of base library DLL") \ 306 \ 307 product(bool, InlineNatives, true, DIAGNOSTIC, \ 308 "Inline natives that are known to be part of base library DLL") \ 309 \ 310 product(bool, InlineMathNatives, true, DIAGNOSTIC, \ 311 "Inline SinD, CosD, etc.") \ 312 \ 313 product(bool, InlineClassNatives, true, DIAGNOSTIC, \ 314 "Inline Class.isInstance, etc") \ 315 \ 316 product(bool, InlineThreadNatives, true, DIAGNOSTIC, \ 317 "Inline Thread.currentThread, etc") \ 318 \ 319 product(bool, InlineUnsafeOps, true, DIAGNOSTIC, \ 320 "Inline memory ops (native methods) from Unsafe") \ 321 \ 322 product(bool, UseAESIntrinsics, false, DIAGNOSTIC, \ 323 "Use intrinsics for AES versions of crypto") \ 324 \ 325 product(bool, UseAESCTRIntrinsics, false, DIAGNOSTIC, \ 326 "Use intrinsics for the paralleled version of AES/CTR crypto") \ 327 \ 328 product(bool, UseChaCha20Intrinsics, false, DIAGNOSTIC, \ 329 "Use intrinsics for the vectorized version of ChaCha20") \ 330 \ 331 product(bool, UseMD5Intrinsics, false, DIAGNOSTIC, \ 332 "Use intrinsics for MD5 crypto hash function") \ 333 \ 334 product(bool, UseSHA1Intrinsics, false, DIAGNOSTIC, \ 335 "Use intrinsics for SHA-1 crypto hash function. " \ 336 "Requires that UseSHA is enabled.") \ 337 \ 338 product(bool, UseSHA256Intrinsics, false, DIAGNOSTIC, \ 339 "Use intrinsics for SHA-224 and SHA-256 crypto hash functions. " \ 340 "Requires that UseSHA is enabled.") \ 341 \ 342 product(bool, UseSHA512Intrinsics, false, DIAGNOSTIC, \ 343 "Use intrinsics for SHA-384 and SHA-512 crypto hash functions. " \ 344 "Requires that UseSHA is enabled.") \ 345 \ 346 product(bool, UseSHA3Intrinsics, false, DIAGNOSTIC, \ 347 "Use intrinsics for SHA3 crypto hash function. " \ 348 "Requires that UseSHA is enabled.") \ 349 \ 350 product(bool, UseCRC32Intrinsics, false, DIAGNOSTIC, \ 351 "use intrinsics for java.util.zip.CRC32") \ 352 \ 353 product(bool, UseCRC32CIntrinsics, false, DIAGNOSTIC, \ 354 "use intrinsics for java.util.zip.CRC32C") \ 355 \ 356 product(bool, UseAdler32Intrinsics, false, DIAGNOSTIC, \ 357 "use intrinsics for java.util.zip.Adler32") \ 358 \ 359 product(bool, UseVectorizedMismatchIntrinsic, false, DIAGNOSTIC, \ 360 "Enables intrinsification of ArraysSupport.vectorizedMismatch()") \ 361 \ 362 product(bool, UseVectorizedHashCodeIntrinsic, false, DIAGNOSTIC, \ 363 "Enables intrinsification of ArraysSupport.vectorizedHashCode()") \ 364 \ 365 product(bool, UseCopySignIntrinsic, false, DIAGNOSTIC, \ 366 "Enables intrinsification of Math.copySign") \ 367 \ 368 product(bool, UseSignumIntrinsic, false, DIAGNOSTIC, \ 369 "Enables intrinsification of Math.signum") \ 370 \ 371 product_pd(bool, DelayCompilerStubsGeneration, DIAGNOSTIC, \ 372 "Use Compiler thread for compiler's stubs generation") \ 373 \ 374 product(ccstrlist, DisableIntrinsic, "", DIAGNOSTIC, \ 375 "do not expand intrinsics whose (internal) names appear here") \ 376 constraint(DisableIntrinsicConstraintFunc,AfterErgo) \ 377 \ 378 product(ccstrlist, ControlIntrinsic, "", DIAGNOSTIC, \ 379 "Control intrinsics using a list of +/- (internal) names, " \ 380 "separated by commas") \ 381 constraint(ControlIntrinsicConstraintFunc,AfterErgo) \ 382 \ 383 develop(bool, TraceCallFixup, false, \ 384 "Trace all call fixups") \ 385 \ 386 develop(bool, DeoptimizeALot, false, \ 387 "Deoptimize at every exit from the runtime system") \ 388 \ 389 develop(ccstrlist, DeoptimizeOnlyAt, "", \ 390 "A comma separated list of bcis to deoptimize at") \ 391 \ 392 develop(bool, DeoptimizeRandom, false, \ 393 "Deoptimize random frames on random exit from the runtime system")\ 394 \ 395 develop(bool, ZombieALot, false, \ 396 "Create non-entrant nmethods at exit from the runtime system") \ 397 \ 398 develop(bool, WalkStackALot, false, \ 399 "Trace stack (no print) at every exit from the runtime system") \ 400 \ 401 develop(bool, DeoptimizeObjectsALot, false, \ 402 "For testing purposes concurrent threads revert optimizations " \ 403 "based on escape analysis at intervals given with " \ 404 "DeoptimizeObjectsALotInterval=n. The thread count is given " \ 405 "with DeoptimizeObjectsALotThreadCountSingle and " \ 406 "DeoptimizeObjectsALotThreadCountAll.") \ 407 \ 408 develop(uint64_t, DeoptimizeObjectsALotInterval, 5, \ 409 "Interval for DeoptimizeObjectsALot.") \ 410 range(0, max_jlong) \ 411 \ 412 develop(int, DeoptimizeObjectsALotThreadCountSingle, 1, \ 413 "The number of threads that revert optimizations based on " \ 414 "escape analysis for a single thread if DeoptimizeObjectsALot " \ 415 "is enabled. The target thread is selected round robin." ) \ 416 range(0, max_jint) \ 417 \ 418 develop(int, DeoptimizeObjectsALotThreadCountAll, 1, \ 419 "The number of threads that revert optimizations based on " \ 420 "escape analysis for all threads if DeoptimizeObjectsALot " \ 421 "is enabled." ) \ 422 range(0, max_jint) \ 423 \ 424 develop(bool, VerifyLastFrame, false, \ 425 "Verify oops on last frame on entry to VM") \ 426 \ 427 product(bool, SafepointTimeout, false, \ 428 "Time out and warn or fail after SafepointTimeoutDelay " \ 429 "milliseconds if failed to reach safepoint") \ 430 \ 431 product(bool, AbortVMOnSafepointTimeout, false, DIAGNOSTIC, \ 432 "Abort upon failure to reach safepoint (see SafepointTimeout)") \ 433 \ 434 product(uint64_t, AbortVMOnSafepointTimeoutDelay, 0, DIAGNOSTIC, \ 435 "Delay in milliseconds for option AbortVMOnSafepointTimeout") \ 436 range(0, max_jlong) \ 437 \ 438 product(bool, AbortVMOnVMOperationTimeout, false, DIAGNOSTIC, \ 439 "Abort upon failure to complete VM operation promptly") \ 440 \ 441 product(intx, AbortVMOnVMOperationTimeoutDelay, 1000, DIAGNOSTIC, \ 442 "Delay in milliseconds for option AbortVMOnVMOperationTimeout") \ 443 range(0, max_intx) \ 444 \ 445 product(bool, MaxFDLimit, true, \ 446 "Bump the number of file descriptors to maximum (Unix only)") \ 447 \ 448 product(bool, LogEvents, true, DIAGNOSTIC, \ 449 "Enable the various ring buffer event logs") \ 450 \ 451 product(int, LogEventsBufferEntries, 20, DIAGNOSTIC, \ 452 "Number of ring buffer event logs") \ 453 range(1, NOT_LP64(1*K) LP64_ONLY(1*M)) \ 454 \ 455 product(bool, BytecodeVerificationRemote, true, DIAGNOSTIC, \ 456 "Enable the Java bytecode verifier for remote classes") \ 457 \ 458 product(bool, BytecodeVerificationLocal, false, DIAGNOSTIC, \ 459 "Enable the Java bytecode verifier for local classes") \ 460 \ 461 develop(bool, VerifyStackAtCalls, false, \ 462 "Verify that the stack pointer is unchanged after calls") \ 463 \ 464 develop(bool, TraceJavaAssertions, false, \ 465 "Trace java language assertions") \ 466 \ 467 develop(bool, VerifyCodeCache, false, \ 468 "Verify code cache on memory allocation/deallocation") \ 469 \ 470 develop(bool, ZapResourceArea, trueInDebug, \ 471 "Zap freed resource/arena space") \ 472 \ 473 develop(bool, ZapVMHandleArea, trueInDebug, \ 474 "Zap freed VM handle space") \ 475 \ 476 develop(bool, ZapStackSegments, trueInDebug, \ 477 "Zap allocated/freed stack segments") \ 478 \ 479 develop(bool, ZapUnusedHeapArea, trueInDebug, \ 480 "Zap unused heap space") \ 481 \ 482 develop(bool, ZapFillerObjects, trueInDebug, \ 483 "Zap filler objects") \ 484 \ 485 develop(bool, ZapTLAB, trueInDebug, \ 486 "Zap allocated TLABs") \ 487 \ 488 product(bool, ExecutingUnitTests, false, \ 489 "Whether the JVM is running unit tests or not") \ 490 \ 491 develop(uint, ErrorHandlerTest, 0, \ 492 "If > 0, provokes an error after VM initialization; the value " \ 493 "determines which error to provoke. See controlled_crash() " \ 494 "in vmError.cpp.") \ 495 range(0, 17) \ 496 \ 497 develop(uint, TestCrashInErrorHandler, 0, \ 498 "If > 0, provokes an error inside VM error handler (a secondary " \ 499 "crash). see controlled_crash() in vmError.cpp") \ 500 range(0, 17) \ 501 \ 502 develop(bool, TestSafeFetchInErrorHandler, false , \ 503 "If true, tests SafeFetch inside error handler.") \ 504 \ 505 develop(bool, TestUnresponsiveErrorHandler, false, \ 506 "If true, simulates an unresponsive error handler.") \ 507 \ 508 develop(bool, Verbose, false, \ 509 "Print additional debugging information from other modes") \ 510 \ 511 develop(bool, PrintMiscellaneous, false, \ 512 "Print uncategorized debugging information (requires +Verbose)") \ 513 \ 514 develop(bool, WizardMode, false, \ 515 "Print much more debugging information") \ 516 \ 517 product(bool, ShowMessageBoxOnError, false, \ 518 "Keep process alive on VM fatal error") \ 519 \ 520 product(bool, CreateCoredumpOnCrash, true, \ 521 "Create core/mini dump on VM fatal error") \ 522 \ 523 product(uint64_t, ErrorLogTimeout, 2 * 60, \ 524 "Timeout, in seconds, to limit the time spent on writing an " \ 525 "error log in case of a crash.") \ 526 range(0, (uint64_t)max_jlong/1000) \ 527 \ 528 product(bool, ErrorLogSecondaryErrorDetails, false, DIAGNOSTIC, \ 529 "If enabled, show details on secondary crashes in the error log") \ 530 \ 531 develop(intx, TraceDwarfLevel, 0, \ 532 "Debug levels for the dwarf parser") \ 533 range(0, 4) \ 534 \ 535 product(bool, SuppressFatalErrorMessage, false, \ 536 "Report NO fatal error message (avoid deadlock)") \ 537 \ 538 product(ccstrlist, OnError, "", \ 539 "Run user-defined commands on fatal error; see VMError.cpp " \ 540 "for examples") \ 541 \ 542 product(ccstrlist, OnOutOfMemoryError, "", \ 543 "Run user-defined commands on first java.lang.OutOfMemoryError " \ 544 "thrown from JVM") \ 545 \ 546 product(bool, HeapDumpBeforeFullGC, false, MANAGEABLE, \ 547 "Dump heap to file before any major stop-the-world GC " \ 548 "(also see FullGCHeapDumpLimit, HeapDumpPath, HeapDumpGzipLevel)")\ 549 \ 550 product(bool, HeapDumpAfterFullGC, false, MANAGEABLE, \ 551 "Dump heap to file after any major stop-the-world GC " \ 552 "(also see FullGCHeapDumpLimit, HeapDumpPath, HeapDumpGzipLevel)")\ 553 \ 554 product(uint, FullGCHeapDumpLimit, 0, MANAGEABLE, \ 555 "Limit the number of heap dumps triggered by " \ 556 "HeapDumpBeforeFullGC or HeapDumpAfterFullGC " \ 557 "(0 means no limit)") \ 558 \ 559 product(bool, HeapDumpOnOutOfMemoryError, false, MANAGEABLE, \ 560 "Dump heap to file when java.lang.OutOfMemoryError is thrown " \ 561 "from JVM " \ 562 "(also see HeapDumpPath, HeapDumpGzipLevel)") \ 563 \ 564 product(ccstr, HeapDumpPath, nullptr, MANAGEABLE, \ 565 "When HeapDumpOnOutOfMemoryError, HeapDumpBeforeFullGC " \ 566 "or HeapDumpAfterFullGC is on, the path (filename or " \ 567 "directory) of the dump file (defaults to java_pid<pid>.hprof " \ 568 "in the working directory)") \ 569 \ 570 product(int, HeapDumpGzipLevel, 0, MANAGEABLE, \ 571 "When HeapDumpOnOutOfMemoryError, HeapDumpBeforeFullGC " \ 572 "or HeapDumpAfterFullGC is on, the gzip compression " \ 573 "level of the dump file. 0 (the default) disables gzip " \ 574 "compression. Otherwise the level must be between 1 and 9.") \ 575 range(0, 9) \ 576 \ 577 product(ccstr, NativeMemoryTracking, DEBUG_ONLY("summary") NOT_DEBUG("off"), \ 578 "Native memory tracking options") \ 579 \ 580 product(bool, PrintNMTStatistics, false, DIAGNOSTIC, \ 581 "Print native memory tracking summary data if it is on") \ 582 \ 583 product(bool, LogCompilation, false, DIAGNOSTIC, \ 584 "Log compilation activity in detail to LogFile") \ 585 \ 586 product(bool, PrintCompilation, false, \ 587 "Print compilations") \ 588 \ 589 product(intx, RepeatCompilation, 0, DIAGNOSTIC, \ 590 "Repeat compilation without installing code (number of times)") \ 591 range(0, max_jint) \ 592 \ 593 product(bool, PrintExtendedThreadInfo, false, \ 594 "Print more information in thread dump") \ 595 \ 596 product(intx, ScavengeRootsInCode, 2, DIAGNOSTIC, \ 597 "0: do not allow scavengable oops in the code cache; " \ 598 "1: allow scavenging from the code cache; " \ 599 "2: emit as many constants as the compiler can see") \ 600 range(0, 2) \ 601 \ 602 product(bool, AlwaysRestoreFPU, false, \ 603 "Restore the FPU control word after every JNI call (expensive)") \ 604 \ 605 product(bool, PrintCompilation2, false, DIAGNOSTIC, \ 606 "Print additional statistics per compilation") \ 607 \ 608 product(bool, PrintAdapterHandlers, false, DIAGNOSTIC, \ 609 "Print code generated for i2c/c2i adapters") \ 610 \ 611 product(bool, VerifyAdapterCalls, trueInDebug, DIAGNOSTIC, \ 612 "Verify that i2c/c2i adapters are called properly") \ 613 \ 614 develop(bool, VerifyAdapterSharing, false, \ 615 "Verify that the code for shared adapters is the equivalent") \ 616 \ 617 product(bool, PrintAssembly, false, DIAGNOSTIC, \ 618 "Print assembly code (using external disassembler.so)") \ 619 \ 620 product(ccstr, PrintAssemblyOptions, nullptr, DIAGNOSTIC, \ 621 "Print options string passed to disassembler.so") \ 622 \ 623 develop(bool, PrintNMethodStatistics, false, \ 624 "Print a summary statistic for the generated nmethods") \ 625 \ 626 product(bool, PrintNMethods, false, DIAGNOSTIC, \ 627 "Print assembly code for nmethods when generated") \ 628 \ 629 product(bool, PrintNativeNMethods, false, DIAGNOSTIC, \ 630 "Print assembly code for native nmethods when generated") \ 631 \ 632 develop(bool, PrintDebugInfo, false, \ 633 "Print debug information for all nmethods when generated") \ 634 \ 635 develop(bool, PrintRelocations, false, \ 636 "Print relocation information for all nmethods when generated") \ 637 \ 638 develop(bool, PrintDependencies, false, \ 639 "Print dependency information for all nmethods when generated") \ 640 \ 641 develop(bool, PrintExceptionHandlers, false, \ 642 "Print exception handler tables for all nmethods when generated") \ 643 \ 644 develop(bool, StressCompiledExceptionHandlers, false, \ 645 "Exercise compiled exception handlers") \ 646 \ 647 develop(bool, InterceptOSException, false, \ 648 "Start debugger when an implicit OS (e.g. null pointer) " \ 649 "exception happens") \ 650 \ 651 product(bool, PrintCodeCache, false, \ 652 "Print the code cache memory usage when exiting") \ 653 \ 654 develop(bool, PrintCodeCache2, false, \ 655 "Print detailed usage information on the code cache when exiting")\ 656 \ 657 product(bool, PrintCodeCacheOnCompilation, false, \ 658 "Print the code cache memory usage each time a method is " \ 659 "compiled") \ 660 \ 661 product(bool, PrintCodeHeapAnalytics, false, DIAGNOSTIC, \ 662 "Print code heap usage statistics on exit and on full condition") \ 663 \ 664 product(bool, PrintStubCode, false, DIAGNOSTIC, \ 665 "Print generated stub code") \ 666 \ 667 product(bool, StackTraceInThrowable, true, \ 668 "Collect backtrace in throwable when exception happens") \ 669 \ 670 product(bool, OmitStackTraceInFastThrow, true, \ 671 "Omit backtraces for some 'hot' exceptions in optimized code") \ 672 \ 673 product(bool, ShowCodeDetailsInExceptionMessages, true, MANAGEABLE, \ 674 "Show exception messages from RuntimeExceptions that contain " \ 675 "snippets of the failing code. Disable this to improve privacy.") \ 676 \ 677 product(bool, PrintWarnings, true, \ 678 "Print JVM warnings to output stream") \ 679 \ 680 develop(bool, RegisterReferences, true, \ 681 "Tell whether the VM should register soft/weak/final/phantom " \ 682 "references") \ 683 \ 684 develop(bool, PrintCodeCacheExtension, false, \ 685 "Print extension of code cache") \ 686 \ 687 develop(bool, UsePrivilegedStack, true, \ 688 "Enable the security JVM functions") \ 689 \ 690 product(bool, ClassUnloading, true, \ 691 "Do unloading of classes") \ 692 \ 693 product(bool, ClassUnloadingWithConcurrentMark, true, \ 694 "Do unloading of classes with a concurrent marking cycle") \ 695 \ 696 develop(bool, PrintSystemDictionaryAtExit, false, \ 697 "Print the system dictionary at exit") \ 698 \ 699 develop(bool, PrintClassLoaderDataGraphAtExit, false, \ 700 "Print the class loader data graph at exit") \ 701 \ 702 product(bool, AllowParallelDefineClass, false, \ 703 "Allow parallel defineClass requests for class loaders " \ 704 "registering as parallel capable") \ 705 \ 706 product_pd(bool, DontYieldALot, \ 707 "(Deprecated) Throw away obvious excess yield calls") \ 708 \ 709 product(bool, DisablePrimordialThreadGuardPages, false, EXPERIMENTAL, \ 710 "Disable the use of stack guard pages if the JVM is loaded " \ 711 "on the primordial process thread") \ 712 \ 713 product(bool, DoJVMTIVirtualThreadTransitions, true, EXPERIMENTAL, \ 714 "Do JVMTI virtual thread mount/unmount transitions " \ 715 "(disabling this flag implies no JVMTI events are posted)") \ 716 \ 717 /* notice: the max range value here is max_jint, not max_intx */ \ 718 /* because of overflow issue */ \ 719 product(intx, AsyncDeflationInterval, 250, DIAGNOSTIC, \ 720 "Async deflate idle monitors every so many milliseconds when " \ 721 "MonitorUsedDeflationThreshold is exceeded (0 is off).") \ 722 range(0, max_jint) \ 723 \ 724 /* notice: the max range value here is max_jint, not max_intx */ \ 725 /* because of overflow issue */ \ 726 product(intx, GuaranteedAsyncDeflationInterval, 60000, DIAGNOSTIC, \ 727 "Async deflate idle monitors every so many milliseconds even " \ 728 "when MonitorUsedDeflationThreshold is NOT exceeded (0 is off).") \ 729 range(0, max_jint) \ 730 \ 731 product(size_t, AvgMonitorsPerThreadEstimate, 1024, DIAGNOSTIC, \ 732 "Used to estimate a variable ceiling based on number of threads " \ 733 "for use with MonitorUsedDeflationThreshold (0 is off).") \ 734 range(0, max_uintx) \ 735 \ 736 /* notice: the max range value here is max_jint, not max_intx */ \ 737 /* because of overflow issue */ \ 738 product(intx, MonitorDeflationMax, 1000000, DIAGNOSTIC, \ 739 "The maximum number of monitors to deflate, unlink and delete " \ 740 "at one time (minimum is 1024).") \ 741 range(1024, max_jint) \ 742 \ 743 product(intx, MonitorUnlinkBatch, 500, DIAGNOSTIC, \ 744 "The maximum number of monitors to unlink in one batch. ") \ 745 range(1, max_jint) \ 746 \ 747 product(int, MonitorUsedDeflationThreshold, 90, DIAGNOSTIC, \ 748 "Percentage of used monitors before triggering deflation (0 is " \ 749 "off). The check is performed on AsyncDeflationInterval or " \ 750 "GuaranteedAsyncDeflationInterval, whichever is lower.") \ 751 range(0, 100) \ 752 \ 753 product(uintx, NoAsyncDeflationProgressMax, 3, DIAGNOSTIC, \ 754 "Max number of no progress async deflation attempts to tolerate " \ 755 "before adjusting the in_use_list_ceiling up (0 is off).") \ 756 range(0, max_uintx) \ 757 \ 758 product(intx, hashCode, 5, EXPERIMENTAL, \ 759 "(Unstable) select hashCode generation algorithm") \ 760 \ 761 product(bool, ReduceSignalUsage, false, \ 762 "Reduce the use of OS signals in Java and/or the VM") \ 763 \ 764 develop(bool, LoadLineNumberTables, true, \ 765 "Tell whether the class file parser loads line number tables") \ 766 \ 767 develop(bool, LoadLocalVariableTables, true, \ 768 "Tell whether the class file parser loads local variable tables") \ 769 \ 770 develop(bool, LoadLocalVariableTypeTables, true, \ 771 "Tell whether the class file parser loads local variable type" \ 772 "tables") \ 773 \ 774 product(bool, AllowUserSignalHandlers, false, \ 775 "Application will install primary signal handlers for the JVM " \ 776 "(Unix only)") \ 777 \ 778 product(bool, UseSignalChaining, true, \ 779 "Use signal-chaining to invoke signal handlers installed " \ 780 "by the application (Unix only)") \ 781 \ 782 product(bool, RestoreMXCSROnJNICalls, false, \ 783 "Restore MXCSR when returning from JNI calls") \ 784 \ 785 product(bool, CheckJNICalls, false, \ 786 "Verify all arguments to JNI calls") \ 787 \ 788 product(bool, UseFastJNIAccessors, true, \ 789 "Use optimized versions of Get<Primitive>Field") \ 790 \ 791 product(intx, MaxJNILocalCapacity, 65536, \ 792 "Maximum allowable local JNI handle capacity to " \ 793 "EnsureLocalCapacity() and PushLocalFrame(), " \ 794 "where <= 0 is unlimited, default: 65536") \ 795 range(min_intx, max_intx) \ 796 \ 797 product(bool, EagerXrunInit, false, \ 798 "Eagerly initialize -Xrun libraries; allows startup profiling, " \ 799 "but not all -Xrun libraries may support the state of the VM " \ 800 "at this time") \ 801 \ 802 product(bool, PreserveAllAnnotations, false, \ 803 "(Deprecated) Preserve RuntimeInvisibleAnnotations as well " \ 804 "as RuntimeVisibleAnnotations") \ 805 \ 806 develop(uintx, PreallocatedOutOfMemoryErrorCount, 4, \ 807 "Number of OutOfMemoryErrors preallocated with backtrace") \ 808 \ 809 product(bool, UseXMMForArrayCopy, false, \ 810 "Use SSE2 MOVQ instruction for Arraycopy") \ 811 \ 812 develop(bool, PrintFieldLayout, false, \ 813 "Print field layout for each class") \ 814 \ 815 /* Need to limit the extent of the padding to reasonable size. */\ 816 /* 8K is well beyond the reasonable HW cache line size, even with */\ 817 /* aggressive prefetching, while still leaving the room for segregating */\ 818 /* among the distinct pages. */\ 819 product(int, ContendedPaddingWidth, 128, \ 820 "How many bytes to pad the fields/classes marked @Contended with")\ 821 range(0, 8192) \ 822 constraint(ContendedPaddingWidthConstraintFunc,AfterErgo) \ 823 \ 824 product(bool, EnableContended, true, \ 825 "Enable @Contended annotation support") \ 826 \ 827 product(bool, RestrictContended, true, \ 828 "Restrict @Contended to trusted classes") \ 829 \ 830 product(int, DiagnoseSyncOnValueBasedClasses, 0, DIAGNOSTIC, \ 831 "Detect and take action upon identifying synchronization on " \ 832 "value based classes. Modes: " \ 833 "0: off; " \ 834 "1: exit with fatal error; " \ 835 "2: log message to stdout. Output file can be specified with " \ 836 " -Xlog:valuebasedclasses. If JFR is running it will " \ 837 " also generate JFR events.") \ 838 range(0, 2) \ 839 \ 840 product(bool, ExitOnOutOfMemoryError, false, \ 841 "JVM exits on the first occurrence of an out-of-memory error " \ 842 "thrown from JVM") \ 843 \ 844 product(bool, CrashOnOutOfMemoryError, false, \ 845 "JVM aborts, producing an error log and core/mini dump, on the " \ 846 "first occurrence of an out-of-memory error thrown from JVM") \ 847 \ 848 product(intx, UserThreadWaitAttemptsAtExit, 30, \ 849 "The number of times to wait for user threads to stop executing " \ 850 "native code during JVM exit. Each wait lasts 10 milliseconds. " \ 851 "The maximum number of waits is 1000, to wait at most 10 " \ 852 "seconds.") \ 853 range(0, 1000) \ 854 \ 855 /* tracing */ \ 856 \ 857 develop(bool, StressRewriter, false, \ 858 "Stress linktime bytecode rewriting") \ 859 \ 860 product(ccstr, TraceJVMTI, nullptr, \ 861 "Trace flags for JVMTI functions and events") \ 862 \ 863 product(bool, StressLdcRewrite, false, DIAGNOSTIC, \ 864 "Force ldc -> ldc_w rewrite during RedefineClasses. " \ 865 "This option can change an EMCP method into an obsolete method " \ 866 "and can affect tests that expect specific methods to be EMCP. " \ 867 "This option should be used with caution.") \ 868 \ 869 product(bool, AllowRedefinitionToAddDeleteMethods, false, \ 870 "(Deprecated) Allow redefinition to add and delete private " \ 871 "static or final methods for compatibility with old releases") \ 872 \ 873 develop(bool, TraceBytecodes, false, \ 874 "Trace bytecode execution") \ 875 \ 876 develop(bool, TraceBytecodesTruncated, false, \ 877 "Truncate non control-flow bytecode when tracing bytecode") \ 878 \ 879 develop(bool, VerifyDependencies, trueInDebug, \ 880 "Exercise and verify the compilation dependency mechanism") \ 881 \ 882 develop(bool, TraceNewOopMapGeneration, false, \ 883 "Trace OopMapGeneration") \ 884 \ 885 develop(bool, TraceNewOopMapGenerationDetailed, false, \ 886 "Trace OopMapGeneration: print detailed cell states") \ 887 \ 888 develop(bool, TimeOopMap, false, \ 889 "Time calls to GenerateOopMap::compute_map() in sum") \ 890 \ 891 develop(bool, TimeOopMap2, false, \ 892 "Time calls to GenerateOopMap::compute_map() individually") \ 893 \ 894 develop(bool, TraceOopMapRewrites, false, \ 895 "Trace rewriting of methods during oop map generation") \ 896 \ 897 develop(bool, TraceFinalizerRegistration, false, \ 898 "Trace registration of final references") \ 899 \ 900 product(bool, IgnoreEmptyClassPaths, false, \ 901 "Ignore empty path elements in -classpath") \ 902 \ 903 product(bool, PrintHeapAtSIGBREAK, true, \ 904 "Print heap layout in response to SIGBREAK") \ 905 \ 906 product(bool, PrintClassHistogram, false, MANAGEABLE, \ 907 "Print a histogram of class instances") \ 908 \ 909 product(double, ObjectCountCutOffPercent, 0.5, EXPERIMENTAL, \ 910 "The percentage of the used heap that the instances of a class " \ 911 "must occupy for the class to generate a trace event") \ 912 range(0.0, 100.0) \ 913 \ 914 /* JVMTI heap profiling */ \ 915 \ 916 product(bool, VerifyBeforeIteration, false, DIAGNOSTIC, \ 917 "Verify memory system before JVMTI iteration") \ 918 \ 919 /* compiler */ \ 920 \ 921 /* notice: the max range value here is max_jint, not max_intx */ \ 922 /* because of overflow issue */ \ 923 product(intx, CICompilerCount, CI_COMPILER_COUNT, \ 924 "Number of compiler threads to run") \ 925 range(0, max_jint) \ 926 constraint(CICompilerCountConstraintFunc, AfterErgo) \ 927 \ 928 product(bool, UseDynamicNumberOfCompilerThreads, true, \ 929 "Dynamically choose the number of parallel compiler threads") \ 930 \ 931 product(bool, ReduceNumberOfCompilerThreads, true, DIAGNOSTIC, \ 932 "Reduce the number of parallel compiler threads when they " \ 933 "are not used") \ 934 \ 935 product(bool, TraceCompilerThreads, false, DIAGNOSTIC, \ 936 "Trace creation and removal of compiler threads") \ 937 \ 938 product(ccstr, LogClassLoadingCauseFor, nullptr, \ 939 "Apply -Xlog:class+load+cause* to classes whose fully " \ 940 "qualified name contains this string (\"*\" matches " \ 941 "any class).") \ 942 \ 943 develop(bool, InjectCompilerCreationFailure, false, \ 944 "Inject thread creation failures for " \ 945 "UseDynamicNumberOfCompilerThreads") \ 946 \ 947 develop(bool, GenerateSynchronizationCode, true, \ 948 "generate locking/unlocking code for synchronized methods and " \ 949 "monitors") \ 950 \ 951 product_pd(bool, ImplicitNullChecks, DIAGNOSTIC, \ 952 "Generate code for implicit null checks") \ 953 \ 954 product_pd(bool, TrapBasedNullChecks, \ 955 "Generate code for null checks that uses a cmp and trap " \ 956 "instruction raising SIGTRAP. This is only used if an access to" \ 957 "null (+offset) will not raise a SIGSEGV, i.e.," \ 958 "ImplicitNullChecks don't work (PPC64).") \ 959 \ 960 product(bool, EnableThreadSMRStatistics, trueInDebug, DIAGNOSTIC, \ 961 "Enable Thread SMR Statistics") \ 962 \ 963 product(bool, UseNotificationThread, true, \ 964 "(Deprecated) Use Notification Thread") \ 965 \ 966 product(bool, Inline, true, \ 967 "Enable inlining") \ 968 \ 969 product(bool, ClipInlining, true, \ 970 "Clip inlining if aggregate method exceeds DesiredMethodLimit") \ 971 \ 972 develop(bool, UseCHA, true, \ 973 "Enable CHA") \ 974 \ 975 product(bool, UseVtableBasedCHA, true, DIAGNOSTIC, \ 976 "Use vtable information during CHA") \ 977 \ 978 product(bool, UseTypeProfile, true, \ 979 "Check interpreter profile for historically monomorphic calls") \ 980 \ 981 product(bool, PrintInlining, false, DIAGNOSTIC, \ 982 "Print inlining optimizations") \ 983 \ 984 product(bool, UsePopCountInstruction, false, \ 985 "Use population count instruction") \ 986 \ 987 develop(bool, TraceMethodReplacement, false, \ 988 "Print when methods are replaced do to recompilation") \ 989 \ 990 product(intx, MinPassesBeforeFlush, 10, DIAGNOSTIC, \ 991 "Minimum number of sweeper passes before an nmethod " \ 992 "can be flushed") \ 993 range(0, max_intx) \ 994 \ 995 develop(bool, StressCodeBuffers, false, \ 996 "Exercise code buffer expansion and other rare state changes") \ 997 \ 998 product(bool, DebugNonSafepoints, trueInDebug, DIAGNOSTIC, \ 999 "Generate extra debugging information for non-safepoints in " \ 1000 "nmethods") \ 1001 \ 1002 product(bool, PrintVMOptions, false, \ 1003 "Print flags that appeared on the command line") \ 1004 \ 1005 product(bool, IgnoreUnrecognizedVMOptions, false, \ 1006 "Ignore unrecognized VM options") \ 1007 \ 1008 product(bool, PrintCommandLineFlags, false, \ 1009 "Print flags specified on command line or set by ergonomics") \ 1010 \ 1011 product(bool, PrintFlagsInitial, false, \ 1012 "Print all VM flags before argument processing and exit VM") \ 1013 \ 1014 product(bool, PrintFlagsFinal, false, \ 1015 "Print all VM flags after argument and ergonomic processing") \ 1016 \ 1017 develop(bool, PrintFlagsWithComments, false, \ 1018 "Print all VM flags with default values and descriptions and " \ 1019 "exit") \ 1020 \ 1021 product(bool, PrintFlagsRanges, false, \ 1022 "Print VM flags and their ranges") \ 1023 \ 1024 product(bool, SerializeVMOutput, true, DIAGNOSTIC, \ 1025 "Use a mutex to serialize output to tty and LogFile") \ 1026 \ 1027 product(bool, DisplayVMOutput, true, DIAGNOSTIC, \ 1028 "Display all VM output on the tty, independently of LogVMOutput") \ 1029 \ 1030 product(bool, LogVMOutput, false, DIAGNOSTIC, \ 1031 "Save VM output to LogFile") \ 1032 \ 1033 product(ccstr, LogFile, nullptr, DIAGNOSTIC, \ 1034 "If LogVMOutput or LogCompilation is on, save VM output to " \ 1035 "this file [default: ./hotspot_pid%p.log] (%p replaced with pid)")\ 1036 \ 1037 product(ccstr, ErrorFile, nullptr, \ 1038 "If an error occurs, save the error data to this file " \ 1039 "[default: ./hs_err_pid%p.log] (%p replaced with pid)") \ 1040 \ 1041 product(bool, ExtensiveErrorReports, \ 1042 PRODUCT_ONLY(false) NOT_PRODUCT(true), \ 1043 "Error reports are more extensive.") \ 1044 \ 1045 product(bool, DisplayVMOutputToStderr, false, \ 1046 "If DisplayVMOutput is true, display all VM output to stderr") \ 1047 \ 1048 product(bool, DisplayVMOutputToStdout, false, \ 1049 "If DisplayVMOutput is true, display all VM output to stdout") \ 1050 \ 1051 product(bool, ErrorFileToStderr, false, \ 1052 "If true, error data is printed to stderr instead of a file") \ 1053 \ 1054 product(bool, ErrorFileToStdout, false, \ 1055 "If true, error data is printed to stdout instead of a file") \ 1056 \ 1057 develop(bool, VerifyHeavyMonitors, false, \ 1058 "Checks that no stack locking happens when using " \ 1059 "-XX:LockingMode=0 (LM_MONITOR)") \ 1060 \ 1061 product(bool, PrintStringTableStatistics, false, \ 1062 "print statistics about the StringTable and SymbolTable") \ 1063 \ 1064 product(bool, VerifyStringTableAtExit, false, DIAGNOSTIC, \ 1065 "verify StringTable contents at exit") \ 1066 \ 1067 develop(bool, PrintSymbolTableSizeHistogram, false, \ 1068 "print histogram of the symbol table") \ 1069 \ 1070 product(ccstr, AbortVMOnException, nullptr, DIAGNOSTIC, \ 1071 "Call fatal if this exception is thrown. Example: " \ 1072 "java -XX:AbortVMOnException=java.lang.NullPointerException Foo") \ 1073 \ 1074 product(ccstr, AbortVMOnExceptionMessage, nullptr, DIAGNOSTIC, \ 1075 "Call fatal if the exception pointed by AbortVMOnException " \ 1076 "has this message") \ 1077 \ 1078 develop(bool, DebugVtables, false, \ 1079 "add debugging code to vtable dispatch") \ 1080 \ 1081 product(bool, RangeCheckElimination, true, \ 1082 "Eliminate range checks") \ 1083 \ 1084 develop_pd(bool, UncommonNullCast, \ 1085 "track occurrences of null in casts; adjust compiler tactics") \ 1086 \ 1087 develop(bool, TypeProfileCasts, true, \ 1088 "treat casts like calls for purposes of type profiling") \ 1089 \ 1090 develop(bool, TraceLivenessGen, false, \ 1091 "Trace the generation of liveness analysis information") \ 1092 \ 1093 develop(bool, TraceLivenessQuery, false, \ 1094 "Trace queries of liveness analysis information") \ 1095 \ 1096 develop(bool, CollectIndexSetStatistics, false, \ 1097 "Collect information about IndexSets") \ 1098 \ 1099 develop(int, FastAllocateSizeLimit, 128*K, \ 1100 /* Note: This value is zero mod 1<<13 for a cheap sparc set. */ \ 1101 "Inline allocations larger than this in doublewords must go slow")\ 1102 \ 1103 product_pd(bool, CompactStrings, \ 1104 "Enable Strings to use single byte chars in backing store") \ 1105 \ 1106 product_pd(uint, TypeProfileLevel, \ 1107 "=XYZ, with Z: Type profiling of arguments at call; " \ 1108 "Y: Type profiling of return value at call; " \ 1109 "X: Type profiling of parameters to methods; " \ 1110 "X, Y and Z in 0=off ; 1=jsr292 only; 2=all methods") \ 1111 constraint(TypeProfileLevelConstraintFunc, AfterErgo) \ 1112 \ 1113 product(int, TypeProfileArgsLimit, 2, \ 1114 "max number of call arguments to consider for type profiling") \ 1115 range(0, 16) \ 1116 \ 1117 product(int, TypeProfileParmsLimit, 2, \ 1118 "max number of incoming parameters to consider for type profiling"\ 1119 ", -1 for all") \ 1120 range(-1, 64) \ 1121 \ 1122 /* statistics */ \ 1123 develop(bool, CountCompiledCalls, false, \ 1124 "Count method invocations") \ 1125 \ 1126 develop(bool, ICMissHistogram, false, \ 1127 "Produce histogram of IC misses") \ 1128 \ 1129 /* interpreter */ \ 1130 product_pd(bool, RewriteBytecodes, \ 1131 "Allow rewriting of bytecodes (bytecodes are not immutable)") \ 1132 \ 1133 product_pd(bool, RewriteFrequentPairs, \ 1134 "Rewrite frequently used bytecode pairs into a single bytecode") \ 1135 \ 1136 product(bool, PrintInterpreter, false, DIAGNOSTIC, \ 1137 "Print the generated interpreter code") \ 1138 \ 1139 product(bool, UseInterpreter, true, \ 1140 "Use interpreter for non-compiled methods") \ 1141 \ 1142 develop(bool, UseFastSignatureHandlers, true, \ 1143 "Use fast signature handlers for native calls") \ 1144 \ 1145 product(bool, UseLoopCounter, true, \ 1146 "Increment invocation counter on backward branch") \ 1147 \ 1148 product_pd(bool, UseOnStackReplacement, \ 1149 "Use on stack replacement, calls runtime if invoc. counter " \ 1150 "overflows in loop") \ 1151 \ 1152 develop(bool, TraceOnStackReplacement, false, \ 1153 "Trace on stack replacement") \ 1154 \ 1155 product_pd(bool, PreferInterpreterNativeStubs, \ 1156 "Use always interpreter stubs for native methods invoked via " \ 1157 "interpreter") \ 1158 \ 1159 develop(bool, CountBytecodes, false, \ 1160 "Count number of bytecodes executed") \ 1161 \ 1162 develop(bool, PrintBytecodeHistogram, false, \ 1163 "Print histogram of the executed bytecodes") \ 1164 \ 1165 develop(bool, PrintBytecodePairHistogram, false, \ 1166 "Print histogram of the executed bytecode pairs") \ 1167 \ 1168 product(bool, PrintSignatureHandlers, false, DIAGNOSTIC, \ 1169 "Print code generated for native method signature handlers") \ 1170 \ 1171 develop(bool, VerifyOops, false, \ 1172 "Do plausibility checks for oops") \ 1173 \ 1174 develop(bool, CheckUnhandledOops, false, \ 1175 "Check for unhandled oops in VM code") \ 1176 \ 1177 develop(bool, VerifyJNIFields, trueInDebug, \ 1178 "Verify jfieldIDs for instance fields") \ 1179 \ 1180 develop(bool, VerifyFPU, false, \ 1181 "Verify FPU state (check for NaN's, etc.)") \ 1182 \ 1183 develop(bool, VerifyActivationFrameSize, false, \ 1184 "Verify that activation frame didn't become smaller than its " \ 1185 "minimal size") \ 1186 \ 1187 develop(bool, TraceFrequencyInlining, false, \ 1188 "Trace frequency based inlining") \ 1189 \ 1190 develop_pd(bool, InlineIntrinsics, \ 1191 "Use intrinsics in Interpreter that can be statically resolved") \ 1192 \ 1193 product_pd(bool, ProfileInterpreter, \ 1194 "Profile at the bytecode level during interpretation") \ 1195 \ 1196 develop_pd(bool, ProfileTraps, \ 1197 "Profile deoptimization traps at the bytecode level") \ 1198 \ 1199 product(intx, ProfileMaturityPercentage, 20, \ 1200 "number of method invocations/branches (expressed as % of " \ 1201 "CompileThreshold) before using the method's profile") \ 1202 range(0, 100) \ 1203 \ 1204 product(bool, PrintMethodData, false, DIAGNOSTIC, \ 1205 "Print the results of +ProfileInterpreter at end of run") \ 1206 \ 1207 develop(bool, VerifyDataPointer, trueInDebug, \ 1208 "Verify the method data pointer during interpreter profiling") \ 1209 \ 1210 develop(bool, CrashGCForDumpingJavaThread, false, \ 1211 "Manually make GC thread crash then dump java stack trace; " \ 1212 "Test only") \ 1213 \ 1214 /* compilation */ \ 1215 product(bool, UseCompiler, true, \ 1216 "Use Just-In-Time compilation") \ 1217 \ 1218 develop(intx, CounterHalfLifeTime, 30, \ 1219 "Half-life time of invocation counters (in seconds)") \ 1220 \ 1221 product(bool, AlwaysCompileLoopMethods, false, \ 1222 "When using recompilation, never interpret methods " \ 1223 "containing loops") \ 1224 \ 1225 product(int, AllocatePrefetchStyle, 1, \ 1226 "0 = no prefetch, " \ 1227 "1 = generate prefetch instructions for each allocation, " \ 1228 "2 = use TLAB watermark to gate allocation prefetch, " \ 1229 "3 = generate one prefetch instruction per cache line") \ 1230 range(0, 3) \ 1231 \ 1232 product(int, AllocatePrefetchDistance, -1, \ 1233 "Distance to prefetch ahead of allocation pointer. " \ 1234 "-1: use system-specific value (automatically determined") \ 1235 range(-1, 512) \ 1236 \ 1237 product(int, AllocatePrefetchLines, 3, \ 1238 "Number of lines to prefetch ahead of array allocation pointer") \ 1239 range(1, 64) \ 1240 \ 1241 product(int, AllocateInstancePrefetchLines, 1, \ 1242 "Number of lines to prefetch ahead of instance allocation " \ 1243 "pointer") \ 1244 range(1, 64) \ 1245 \ 1246 product(int, AllocatePrefetchStepSize, 16, \ 1247 "Step size in bytes of sequential prefetch instructions") \ 1248 range(1, 512) \ 1249 constraint(AllocatePrefetchStepSizeConstraintFunc,AfterMemoryInit)\ 1250 \ 1251 product(intx, AllocatePrefetchInstr, 0, \ 1252 "Select instruction to prefetch ahead of allocation pointer") \ 1253 constraint(AllocatePrefetchInstrConstraintFunc, AfterMemoryInit) \ 1254 \ 1255 /* deoptimization */ \ 1256 product(bool, TraceDeoptimization, false, DIAGNOSTIC, \ 1257 "Trace deoptimization") \ 1258 \ 1259 develop(bool, PrintDeoptimizationDetails, false, \ 1260 "Print more information about deoptimization") \ 1261 \ 1262 develop(bool, DebugDeoptimization, false, \ 1263 "Tracing various information while debugging deoptimization") \ 1264 \ 1265 product(double, SelfDestructTimer, 0.0, \ 1266 "Will cause VM to terminate after a given time " \ 1267 "(in fractional minutes) " \ 1268 "(0.0 means off)") \ 1269 range(0.0, (double)max_intx) \ 1270 \ 1271 product(int, MaxJavaStackTraceDepth, 1024, \ 1272 "The maximum number of lines in the stack trace for Java " \ 1273 "exceptions (0 means all)") \ 1274 range(0, max_jint/2) \ 1275 \ 1276 /* notice: the max range value here is max_jint, not max_intx */ \ 1277 /* because of overflow issue */ \ 1278 product(intx, GuaranteedSafepointInterval, 0, DIAGNOSTIC, \ 1279 "Guarantee a safepoint (at least) every so many milliseconds " \ 1280 "(0 means none)") \ 1281 range(0, max_jint) \ 1282 \ 1283 product(intx, ServiceThreadCleanupInterval, 1000, DIAGNOSTIC, \ 1284 "Wake the ServiceThread to do periodic cleanup checks every so " \ 1285 "many milliseconds (0 means none)") \ 1286 range(0, max_jint) \ 1287 \ 1288 product(double, SafepointTimeoutDelay, 10000, \ 1289 "Delay in milliseconds for option SafepointTimeout; " \ 1290 "supports sub-millisecond resolution with fractional values.") \ 1291 range(0, max_jlongDouble LP64_ONLY(/MICROUNITS)) \ 1292 \ 1293 product(bool, UseSystemMemoryBarrier, false, \ 1294 "Try to enable system memory barrier if supported by OS") \ 1295 \ 1296 product(intx, NmethodSweepActivity, 4, \ 1297 "Removes cold nmethods from code cache if > 0. Higher values " \ 1298 "result in more aggressive sweeping") \ 1299 range(0, 2000) \ 1300 \ 1301 develop(intx, MallocCatchPtr, -1, \ 1302 "Hit breakpoint when mallocing/freeing this pointer") \ 1303 \ 1304 develop(int, StackPrintLimit, 100, \ 1305 "number of stack frames to print in VM-level stack dump") \ 1306 \ 1307 product(int, ErrorLogPrintCodeLimit, 3, DIAGNOSTIC, \ 1308 "max number of compiled code units to print in error log") \ 1309 range(0, VMError::max_error_log_print_code) \ 1310 \ 1311 develop(int, MaxElementPrintSize, 256, \ 1312 "maximum number of elements to print") \ 1313 \ 1314 develop(intx, MaxSubklassPrintSize, 4, \ 1315 "maximum number of subklasses to print when printing klass") \ 1316 \ 1317 develop(intx, MaxForceInlineLevel, 100, \ 1318 "maximum number of nested calls that are forced for inlining " \ 1319 "(using CompileCommand or marked w/ @ForceInline)") \ 1320 range(0, max_jint) \ 1321 \ 1322 develop(intx, MethodHistogramCutoff, 100, \ 1323 "The cutoff value for method invocation histogram (+CountCalls)") \ 1324 \ 1325 develop(intx, DeoptimizeALotInterval, 5, \ 1326 "Number of exits until DeoptimizeALot kicks in") \ 1327 \ 1328 develop(intx, ZombieALotInterval, 5, \ 1329 "Number of exits until ZombieALot kicks in") \ 1330 \ 1331 product(ccstr, MallocLimit, nullptr, DIAGNOSTIC, \ 1332 "Limit malloc allocation size from VM. Reaching a limit will " \ 1333 "trigger an action (see flag). This feature requires " \ 1334 "NativeMemoryTracking=summary or NativeMemoryTracking=detail." \ 1335 "Usage:" \ 1336 "\"-XX:MallocLimit=<size>[:<flag>]\" sets a total limit." \ 1337 "\"-XX:MallocLimit=<category>:<size>[:<flag>][,<category>:<size>[:<flag>] ...]\"" \ 1338 "sets one or more category-specific limits." \ 1339 "<flag> defines the action upon reaching the limit:" \ 1340 "\"fatal\": end VM with a fatal error at the allocation site" \ 1341 "\"oom\" : will mimic a native OOM" \ 1342 "If <flag> is omitted, \"fatal\" is the default." \ 1343 "Examples:\n" \ 1344 "-XX:MallocLimit=2g" \ 1345 "-XX:MallocLimit=2g:oom" \ 1346 "-XX:MallocLimit=compiler:200m:oom,code:100m") \ 1347 \ 1348 product(intx, TypeProfileWidth, 2, \ 1349 "Number of receiver types to record in call/cast profile") \ 1350 range(0, 8) \ 1351 \ 1352 develop(intx, BciProfileWidth, 2, \ 1353 "Number of return bci's to record in ret profile") \ 1354 \ 1355 product(intx, PerMethodRecompilationCutoff, 400, \ 1356 "After recompiling N times, stay in the interpreter (-1=>'Inf')") \ 1357 range(-1, max_intx) \ 1358 \ 1359 product(intx, PerBytecodeRecompilationCutoff, 200, \ 1360 "Per-BCI limit on repeated recompilation (-1=>'Inf')") \ 1361 range(-1, max_intx) \ 1362 \ 1363 product(intx, PerMethodTrapLimit, 100, \ 1364 "Limit on traps (of one kind) in a method (includes inlines)") \ 1365 range(0, max_jint) \ 1366 \ 1367 product(intx, PerMethodSpecTrapLimit, 5000, EXPERIMENTAL, \ 1368 "Limit on speculative traps (of one kind) in a method " \ 1369 "(includes inlines)") \ 1370 range(0, max_jint) \ 1371 \ 1372 product(intx, PerBytecodeTrapLimit, 4, \ 1373 "Limit on traps (of one kind) at a particular BCI") \ 1374 range(0, max_jint) \ 1375 \ 1376 product(int, SpecTrapLimitExtraEntries, 3, EXPERIMENTAL, \ 1377 "Extra method data trap entries for speculation") \ 1378 \ 1379 product(double, InlineFrequencyRatio, 0.25, DIAGNOSTIC, \ 1380 "Ratio of call site execution to caller method invocation") \ 1381 \ 1382 product(double, MinInlineFrequencyRatio, 0.0085, DIAGNOSTIC, \ 1383 "Minimum ratio of call site execution to caller method" \ 1384 "invocation to be considered for inlining") \ 1385 \ 1386 develop(intx, InlineThrowCount, 50, \ 1387 "Force inlining of interpreted methods that throw this often") \ 1388 range(0, max_jint) \ 1389 \ 1390 develop(intx, InlineThrowMaxSize, 200, \ 1391 "Force inlining of throwing methods smaller than this") \ 1392 range(0, max_jint) \ 1393 \ 1394 product(size_t, MetaspaceSize, NOT_LP64(16 * M) LP64_ONLY(21 * M), \ 1395 "Initial threshold (in bytes) at which a garbage collection " \ 1396 "is done to reduce Metaspace usage") \ 1397 constraint(MetaspaceSizeConstraintFunc,AfterErgo) \ 1398 \ 1399 product(size_t, MaxMetaspaceSize, max_uintx, \ 1400 "Maximum size of Metaspaces (in bytes)") \ 1401 constraint(MaxMetaspaceSizeConstraintFunc,AfterErgo) \ 1402 \ 1403 product(size_t, CompressedClassSpaceSize, 1*G, \ 1404 "Maximum size of class area in Metaspace when compressed " \ 1405 "class pointers are used") \ 1406 range(1*M, LP64_ONLY(4*G) NOT_LP64(max_uintx)) \ 1407 \ 1408 develop(size_t, CompressedClassSpaceBaseAddress, 0, \ 1409 "Force the class space to be allocated at this address or " \ 1410 "fails VM initialization (requires -Xshare=off.") \ 1411 \ 1412 develop(bool, RandomizeClassSpaceLocation, true, \ 1413 "Randomize location of class space.") \ 1414 \ 1415 product(bool, PrintMetaspaceStatisticsAtExit, false, DIAGNOSTIC, \ 1416 "Print metaspace statistics upon VM exit.") \ 1417 \ 1418 develop(bool, MetaspaceGuardAllocations, false, \ 1419 "Metapace allocations are guarded.") \ 1420 \ 1421 product(uintx, MinHeapFreeRatio, 40, MANAGEABLE, \ 1422 "The minimum percentage of heap free after GC to avoid expansion."\ 1423 " For most GCs this applies to the old generation. In G1 and" \ 1424 " ParallelGC it applies to the whole heap.") \ 1425 range(0, 100) \ 1426 constraint(MinHeapFreeRatioConstraintFunc,AfterErgo) \ 1427 \ 1428 product(uintx, MaxHeapFreeRatio, 70, MANAGEABLE, \ 1429 "The maximum percentage of heap free after GC to avoid shrinking."\ 1430 " For most GCs this applies to the old generation. In G1 and" \ 1431 " ParallelGC it applies to the whole heap.") \ 1432 range(0, 100) \ 1433 constraint(MaxHeapFreeRatioConstraintFunc,AfterErgo) \ 1434 \ 1435 product(intx, SoftRefLRUPolicyMSPerMB, 1000, \ 1436 "Number of milliseconds per MB of free space in the heap") \ 1437 range(0, max_intx) \ 1438 constraint(SoftRefLRUPolicyMSPerMBConstraintFunc,AfterMemoryInit) \ 1439 \ 1440 product(size_t, MinHeapDeltaBytes, ScaleForWordSize(128*K), \ 1441 "The minimum change in heap space due to GC (in bytes)") \ 1442 range(0, max_uintx) \ 1443 \ 1444 product(size_t, MinMetaspaceExpansion, ScaleForWordSize(256*K), \ 1445 "The minimum expansion of Metaspace (in bytes)") \ 1446 range(0, max_uintx) \ 1447 \ 1448 product(uint, MaxMetaspaceFreeRatio, 70, \ 1449 "The maximum percentage of Metaspace free after GC to avoid " \ 1450 "shrinking") \ 1451 range(0, 100) \ 1452 constraint(MaxMetaspaceFreeRatioConstraintFunc,AfterErgo) \ 1453 \ 1454 product(uint, MinMetaspaceFreeRatio, 40, \ 1455 "The minimum percentage of Metaspace free after GC to avoid " \ 1456 "expansion") \ 1457 range(0, 99) \ 1458 constraint(MinMetaspaceFreeRatioConstraintFunc,AfterErgo) \ 1459 \ 1460 product(size_t, MaxMetaspaceExpansion, ScaleForWordSize(4*M), \ 1461 "The maximum expansion of Metaspace without full GC (in bytes)") \ 1462 range(0, max_uintx) \ 1463 \ 1464 /* stack parameters */ \ 1465 product_pd(intx, StackYellowPages, \ 1466 "Number of yellow zone (recoverable overflows) pages of size " \ 1467 "4KB. If pages are bigger yellow zone is aligned up.") \ 1468 range(MIN_STACK_YELLOW_PAGES, (DEFAULT_STACK_YELLOW_PAGES+5)) \ 1469 \ 1470 product_pd(intx, StackRedPages, \ 1471 "Number of red zone (unrecoverable overflows) pages of size " \ 1472 "4KB. If pages are bigger red zone is aligned up.") \ 1473 range(MIN_STACK_RED_PAGES, (DEFAULT_STACK_RED_PAGES+2)) \ 1474 \ 1475 product_pd(intx, StackReservedPages, \ 1476 "Number of reserved zone (reserved to annotated methods) pages" \ 1477 " of size 4KB. If pages are bigger reserved zone is aligned up.") \ 1478 range(MIN_STACK_RESERVED_PAGES, (DEFAULT_STACK_RESERVED_PAGES+10))\ 1479 \ 1480 product(bool, RestrictReservedStack, true, \ 1481 "Restrict @ReservedStackAccess to trusted classes") \ 1482 \ 1483 /* greater stack shadow pages can't generate instruction to bang stack */ \ 1484 product_pd(intx, StackShadowPages, \ 1485 "Number of shadow zone (for overflow checking) pages of size " \ 1486 "4KB. If pages are bigger shadow zone is aligned up. " \ 1487 "This should exceed the depth of the VM and native call stack.") \ 1488 range(MIN_STACK_SHADOW_PAGES, (DEFAULT_STACK_SHADOW_PAGES+30)) \ 1489 \ 1490 product_pd(intx, ThreadStackSize, \ 1491 "Thread Stack Size (in Kbytes)") \ 1492 range(0, 1 * M) \ 1493 \ 1494 product_pd(intx, VMThreadStackSize, \ 1495 "Non-Java Thread Stack Size (in Kbytes)") \ 1496 range(0, max_intx/(1 * K)) \ 1497 \ 1498 product_pd(intx, CompilerThreadStackSize, \ 1499 "Compiler Thread Stack Size (in Kbytes)") \ 1500 range(0, max_intx/(1 * K)) \ 1501 \ 1502 develop_pd(size_t, JVMInvokeMethodSlack, \ 1503 "Stack space (bytes) required for JVM_InvokeMethod to complete") \ 1504 \ 1505 /* code cache parameters */ \ 1506 product_pd(uintx, CodeCacheSegmentSize, EXPERIMENTAL, \ 1507 "Code cache segment size (in bytes) - smallest unit of " \ 1508 "allocation") \ 1509 range(1, 1024) \ 1510 constraint(CodeCacheSegmentSizeConstraintFunc, AfterErgo) \ 1511 \ 1512 product_pd(intx, CodeEntryAlignment, EXPERIMENTAL, \ 1513 "Code entry alignment for generated code (in bytes)") \ 1514 constraint(CodeEntryAlignmentConstraintFunc, AfterErgo) \ 1515 \ 1516 product_pd(intx, OptoLoopAlignment, \ 1517 "Align inner loops to zero relative to this modulus") \ 1518 range(1, 128) \ 1519 constraint(OptoLoopAlignmentConstraintFunc, AfterErgo) \ 1520 \ 1521 product_pd(uintx, InitialCodeCacheSize, \ 1522 "Initial code cache size (in bytes)") \ 1523 constraint(VMPageSizeConstraintFunc, AtParse) \ 1524 \ 1525 develop_pd(uintx, CodeCacheMinimumUseSpace, \ 1526 "Minimum code cache size (in bytes) required to start VM.") \ 1527 range(0, max_uintx) \ 1528 \ 1529 product(bool, SegmentedCodeCache, false, \ 1530 "Use a segmented code cache") \ 1531 \ 1532 product_pd(uintx, ReservedCodeCacheSize, \ 1533 "Reserved code cache size (in bytes) - maximum code cache size") \ 1534 constraint(VMPageSizeConstraintFunc, AtParse) \ 1535 \ 1536 product_pd(uintx, NonProfiledCodeHeapSize, \ 1537 "Size of code heap with non-profiled methods (in bytes)") \ 1538 range(0, max_uintx) \ 1539 \ 1540 product_pd(uintx, ProfiledCodeHeapSize, \ 1541 "Size of code heap with profiled methods (in bytes)") \ 1542 range(0, max_uintx) \ 1543 \ 1544 product_pd(uintx, NonNMethodCodeHeapSize, \ 1545 "Size of code heap with non-nmethods (in bytes)") \ 1546 constraint(VMPageSizeConstraintFunc, AtParse) \ 1547 \ 1548 product_pd(uintx, CodeCacheExpansionSize, \ 1549 "Code cache expansion size (in bytes)") \ 1550 range(32*K, max_uintx) \ 1551 \ 1552 product_pd(uintx, CodeCacheMinBlockLength, DIAGNOSTIC, \ 1553 "Minimum number of segments in a code cache block") \ 1554 range(1, 100) \ 1555 \ 1556 develop(bool, ExitOnFullCodeCache, false, \ 1557 "Exit the VM if we fill the code cache") \ 1558 \ 1559 product(bool, UseCodeCacheFlushing, true, \ 1560 "Remove cold/old nmethods from the code cache") \ 1561 \ 1562 product(double, SweeperThreshold, 15.0, \ 1563 "Threshold when a code cache unloading GC is invoked." \ 1564 "Value is percentage of ReservedCodeCacheSize.") \ 1565 range(0.0, 100.0) \ 1566 \ 1567 product(uintx, StartAggressiveSweepingAt, 10, \ 1568 "Start aggressive sweeping if X[%] of the code cache is free." \ 1569 "Segmented code cache: X[%] of the non-profiled heap." \ 1570 "Non-segmented code cache: X[%] of the total code cache") \ 1571 range(0, 100) \ 1572 \ 1573 /* interpreter debugging */ \ 1574 develop(intx, BinarySwitchThreshold, 5, \ 1575 "Minimal number of lookupswitch entries for rewriting to binary " \ 1576 "switch") \ 1577 \ 1578 develop(intx, StopInterpreterAt, 0, \ 1579 "Stop interpreter execution at specified bytecode number") \ 1580 \ 1581 develop(intx, TraceBytecodesAt, 0, \ 1582 "Trace bytecodes starting with specified bytecode number") \ 1583 \ 1584 develop(intx, TraceBytecodesStopAt, 0, \ 1585 "Stop bytecode tracing at the specified bytecode number") \ 1586 \ 1587 /* Priorities */ \ 1588 product_pd(bool, UseThreadPriorities, "Use native thread priorities") \ 1589 \ 1590 product(int, ThreadPriorityPolicy, 0, \ 1591 "0 : Normal. "\ 1592 " VM chooses priorities that are appropriate for normal "\ 1593 " applications. "\ 1594 " On Windows applications are allowed to use higher native "\ 1595 " priorities. However, with ThreadPriorityPolicy=0, VM will "\ 1596 " not use the highest possible native priority, "\ 1597 " THREAD_PRIORITY_TIME_CRITICAL, as it may interfere with "\ 1598 " system threads. On Linux thread priorities are ignored "\ 1599 " because the OS does not support static priority in "\ 1600 " SCHED_OTHER scheduling class which is the only choice for "\ 1601 " non-root, non-realtime applications. "\ 1602 "1 : Aggressive. "\ 1603 " Java thread priorities map over to the entire range of "\ 1604 " native thread priorities. Higher Java thread priorities map "\ 1605 " to higher native thread priorities. This policy should be "\ 1606 " used with care, as sometimes it can cause performance "\ 1607 " degradation in the application and/or the entire system. On "\ 1608 " Linux/BSD/macOS this policy requires root privilege or an "\ 1609 " extended capability.") \ 1610 range(0, 1) \ 1611 \ 1612 product(bool, ThreadPriorityVerbose, false, \ 1613 "Print priority changes") \ 1614 \ 1615 product(int, CompilerThreadPriority, -1, \ 1616 "The native priority at which compiler threads should run " \ 1617 "(-1 means no change)") \ 1618 range(min_jint, max_jint) \ 1619 \ 1620 product(int, VMThreadPriority, -1, \ 1621 "The native priority at which the VM thread should run " \ 1622 "(-1 means no change)") \ 1623 range(-1, 127) \ 1624 \ 1625 product(int, JavaPriority1_To_OSPriority, -1, \ 1626 "Map Java priorities to OS priorities") \ 1627 range(-1, 127) \ 1628 \ 1629 product(int, JavaPriority2_To_OSPriority, -1, \ 1630 "Map Java priorities to OS priorities") \ 1631 range(-1, 127) \ 1632 \ 1633 product(int, JavaPriority3_To_OSPriority, -1, \ 1634 "Map Java priorities to OS priorities") \ 1635 range(-1, 127) \ 1636 \ 1637 product(int, JavaPriority4_To_OSPriority, -1, \ 1638 "Map Java priorities to OS priorities") \ 1639 range(-1, 127) \ 1640 \ 1641 product(int, JavaPriority5_To_OSPriority, -1, \ 1642 "Map Java priorities to OS priorities") \ 1643 range(-1, 127) \ 1644 \ 1645 product(int, JavaPriority6_To_OSPriority, -1, \ 1646 "Map Java priorities to OS priorities") \ 1647 range(-1, 127) \ 1648 \ 1649 product(int, JavaPriority7_To_OSPriority, -1, \ 1650 "Map Java priorities to OS priorities") \ 1651 range(-1, 127) \ 1652 \ 1653 product(int, JavaPriority8_To_OSPriority, -1, \ 1654 "Map Java priorities to OS priorities") \ 1655 range(-1, 127) \ 1656 \ 1657 product(int, JavaPriority9_To_OSPriority, -1, \ 1658 "Map Java priorities to OS priorities") \ 1659 range(-1, 127) \ 1660 \ 1661 product(int, JavaPriority10_To_OSPriority,-1, \ 1662 "Map Java priorities to OS priorities") \ 1663 range(-1, 127) \ 1664 \ 1665 product(bool, UseCriticalJavaThreadPriority, false, EXPERIMENTAL, \ 1666 "Java thread priority 10 maps to critical scheduling priority") \ 1667 \ 1668 product(bool, UseCriticalCompilerThreadPriority, false, EXPERIMENTAL, \ 1669 "Compiler thread(s) run at critical scheduling priority") \ 1670 \ 1671 develop(intx, NewCodeParameter, 0, \ 1672 "Testing Only: Create a dedicated integer parameter before " \ 1673 "putback") \ 1674 \ 1675 /* new oopmap storage allocation */ \ 1676 develop(intx, MinOopMapAllocation, 8, \ 1677 "Minimum number of OopMap entries in an OopMapSet") \ 1678 \ 1679 /* recompilation */ \ 1680 product_pd(intx, CompileThreshold, \ 1681 "number of interpreted method invocations before (re-)compiling") \ 1682 constraint(CompileThresholdConstraintFunc, AfterErgo) \ 1683 \ 1684 product_pd(bool, TieredCompilation, \ 1685 "Enable tiered compilation") \ 1686 \ 1687 /* Properties for Java libraries */ \ 1688 \ 1689 product(uint64_t, MaxDirectMemorySize, 0, \ 1690 "Maximum total size of NIO direct-buffer allocations. " \ 1691 "Ignored if not explicitly set.") \ 1692 range(0, max_jlong) \ 1693 \ 1694 /* Flags used for temporary code during development */ \ 1695 \ 1696 product(bool, UseNewCode, false, DIAGNOSTIC, \ 1697 "Testing Only: Use the new version while testing") \ 1698 \ 1699 product(bool, UseNewCode2, false, DIAGNOSTIC, \ 1700 "Testing Only: Use the new version while testing") \ 1701 \ 1702 product(bool, UseNewCode3, false, DIAGNOSTIC, \ 1703 "Testing Only: Use the new version while testing") \ 1704 \ 1705 develop(bool, UseDebuggerErgo, false, \ 1706 "Debugging Only: Adjust the VM to be more debugger-friendly. " \ 1707 "Turns on the other UseDebuggerErgo* flags") \ 1708 \ 1709 develop(bool, UseDebuggerErgo1, false, \ 1710 "Debugging Only: Enable workarounds for debugger induced " \ 1711 "os::processor_id() >= os::processor_count() problems") \ 1712 \ 1713 develop(bool, UseDebuggerErgo2, false, \ 1714 "Debugging Only: Limit the number of spawned JVM threads") \ 1715 \ 1716 develop(bool, EnableJVMTIStackDepthAsserts, true, \ 1717 "Enable JVMTI asserts related to stack depth checks") \ 1718 \ 1719 /* flags for performance data collection */ \ 1720 \ 1721 product(bool, UsePerfData, true, \ 1722 "Flag to disable jvmstat instrumentation for performance testing "\ 1723 "and problem isolation purposes") \ 1724 \ 1725 product(bool, PerfDataSaveToFile, false, \ 1726 "Save PerfData memory to hsperfdata_<pid> file on exit") \ 1727 \ 1728 product(ccstr, PerfDataSaveFile, nullptr, \ 1729 "Save PerfData memory to the specified absolute pathname. " \ 1730 "The string %p in the file name (if present) " \ 1731 "will be replaced by pid") \ 1732 \ 1733 product(int, PerfDataSamplingInterval, 50, \ 1734 "Data sampling interval (in milliseconds)") \ 1735 range(PeriodicTask::min_interval, max_jint) \ 1736 constraint(PerfDataSamplingIntervalFunc, AfterErgo) \ 1737 \ 1738 product(bool, PerfDisableSharedMem, false, \ 1739 "Store performance data in standard memory") \ 1740 \ 1741 product(int, PerfDataMemorySize, 32*K, \ 1742 "Size of performance data memory region. Will be rounded " \ 1743 "up to a multiple of the native os page size.") \ 1744 range(128, 32*64*K) \ 1745 \ 1746 product(int, PerfMaxStringConstLength, 1024, \ 1747 "Maximum PerfStringConstant string length before truncation") \ 1748 range(32, 32*K) \ 1749 \ 1750 product(bool, PerfAllowAtExitRegistration, false, \ 1751 "Allow registration of atexit() methods") \ 1752 \ 1753 product(bool, PerfBypassFileSystemCheck, false, \ 1754 "Bypass Win32 file system criteria checks (Windows Only)") \ 1755 \ 1756 product(int, UnguardOnExecutionViolation, 0, \ 1757 "Unguard page and retry on no-execute fault (Win32 only) " \ 1758 "0=off, 1=conservative, 2=aggressive") \ 1759 range(0, 2) \ 1760 \ 1761 /* Serviceability Support */ \ 1762 \ 1763 product(bool, ManagementServer, false, \ 1764 "Create JMX Management Server") \ 1765 \ 1766 product(bool, DisableAttachMechanism, false, \ 1767 "Disable mechanism that allows tools to attach to this VM") \ 1768 \ 1769 product(bool, StartAttachListener, false, \ 1770 "Always start Attach Listener at VM startup") \ 1771 \ 1772 product(bool, EnableDynamicAgentLoading, true, \ 1773 "Allow tools to load agents with the attach mechanism") \ 1774 \ 1775 product(bool, PrintConcurrentLocks, false, MANAGEABLE, \ 1776 "Print java.util.concurrent locks in thread dump") \ 1777 \ 1778 product(bool, PrintMethodHandleStubs, false, DIAGNOSTIC, \ 1779 "Print generated stub code for method handles") \ 1780 \ 1781 product(bool, VerifyMethodHandles, trueInDebug, DIAGNOSTIC, \ 1782 "perform extra checks when constructing method handles") \ 1783 \ 1784 product(bool, ShowHiddenFrames, false, DIAGNOSTIC, \ 1785 "show method handle implementation frames (usually hidden)") \ 1786 \ 1787 product(bool, ShowCarrierFrames, false, DIAGNOSTIC, \ 1788 "show virtual threads' carrier frames in exceptions") \ 1789 \ 1790 product(bool, TrustFinalNonStaticFields, false, EXPERIMENTAL, \ 1791 "trust final non-static declarations for constant folding") \ 1792 \ 1793 product(bool, FoldStableValues, true, DIAGNOSTIC, \ 1794 "Optimize loads from stable fields (marked w/ @Stable)") \ 1795 \ 1796 product(int, UseBootstrapCallInfo, 1, DIAGNOSTIC, \ 1797 "0: when resolving InDy or ConDy, force all BSM arguments to be " \ 1798 "resolved before the bootstrap method is called; 1: when a BSM " \ 1799 "that may accept a BootstrapCallInfo is detected, use that API " \ 1800 "to pass BSM arguments, which allows the BSM to delay their " \ 1801 "resolution; 2+: stress test the BCI API by calling more BSMs " \ 1802 "via that API, instead of with the eagerly-resolved array.") \ 1803 \ 1804 product(bool, PauseAtStartup, false, DIAGNOSTIC, \ 1805 "Causes the VM to pause at startup time and wait for the pause " \ 1806 "file to be removed (default: ./vm.paused.<pid>)") \ 1807 \ 1808 product(ccstr, PauseAtStartupFile, nullptr, DIAGNOSTIC, \ 1809 "The file to create and for whose removal to await when pausing " \ 1810 "at startup. (default: ./vm.paused.<pid>)") \ 1811 \ 1812 product(bool, PauseAtExit, false, DIAGNOSTIC, \ 1813 "Pause and wait for keypress on exit if a debugger is attached") \ 1814 \ 1815 product(bool, DTraceMethodProbes, false, \ 1816 "Enable dtrace tool probes for method-entry and method-exit") \ 1817 \ 1818 product(bool, DTraceAllocProbes, false, \ 1819 "Enable dtrace tool probes for object allocation") \ 1820 \ 1821 product(bool, DTraceMonitorProbes, false, \ 1822 "Enable dtrace tool probes for monitor events") \ 1823 \ 1824 product(bool, RelaxAccessControlCheck, false, \ 1825 "Relax the access control checks in the verifier") \ 1826 \ 1827 product(uintx, StringTableSize, defaultStringTableSize, \ 1828 "Number of buckets in the interned String table " \ 1829 "(will be rounded to nearest higher power of 2)") \ 1830 range(minimumStringTableSize, 16777216ul /* 2^24 */) \ 1831 \ 1832 product(uintx, SymbolTableSize, defaultSymbolTableSize, EXPERIMENTAL, \ 1833 "Number of buckets in the JVM internal Symbol table") \ 1834 range(minimumSymbolTableSize, 16777216ul /* 2^24 */) \ 1835 \ 1836 product(bool, UseStringDeduplication, false, \ 1837 "Use string deduplication") \ 1838 \ 1839 product(uint, StringDeduplicationAgeThreshold, 3, \ 1840 "A string must reach this age (or be promoted to an old region) " \ 1841 "to be considered for deduplication") \ 1842 range(1, markWord::max_age) \ 1843 \ 1844 product(size_t, StringDeduplicationInitialTableSize, 500, EXPERIMENTAL, \ 1845 "Approximate initial number of buckets in the table") \ 1846 range(1, 1 * G) \ 1847 \ 1848 product(double, StringDeduplicationGrowTableLoad, 14.0, EXPERIMENTAL, \ 1849 "Entries per bucket above which the table should be expanded") \ 1850 range(0.1, 1000.0) \ 1851 \ 1852 product(double, StringDeduplicationShrinkTableLoad, 1.0, EXPERIMENTAL, \ 1853 "Entries per bucket below which the table should be shrunk") \ 1854 range(0.01, 100.0) \ 1855 \ 1856 product(double, StringDeduplicationTargetTableLoad, 7.0, EXPERIMENTAL, \ 1857 "Desired entries per bucket when resizing the table") \ 1858 range(0.01, 1000.0) \ 1859 \ 1860 product(size_t, StringDeduplicationCleanupDeadMinimum, 100, EXPERIMENTAL, \ 1861 "Minimum number of dead table entries for cleaning the table") \ 1862 \ 1863 product(int, StringDeduplicationCleanupDeadPercent, 5, EXPERIMENTAL, \ 1864 "Minimum percentage of dead table entries for cleaning the table") \ 1865 range(1, 100) \ 1866 \ 1867 product(bool, StringDeduplicationResizeALot, false, DIAGNOSTIC, \ 1868 "Force more frequent table resizing") \ 1869 \ 1870 product(uint64_t, StringDeduplicationHashSeed, 0, DIAGNOSTIC, \ 1871 "Seed for the table hashing function; 0 requests computed seed") \ 1872 \ 1873 product(bool, WhiteBoxAPI, false, DIAGNOSTIC, \ 1874 "Enable internal testing APIs") \ 1875 \ 1876 product(bool, AlwaysAtomicAccesses, false, EXPERIMENTAL, \ 1877 "Accesses to all variables should always be atomic") \ 1878 \ 1879 product(bool, UseUnalignedAccesses, false, DIAGNOSTIC, \ 1880 "Use unaligned memory accesses in Unsafe") \ 1881 \ 1882 product_pd(bool, PreserveFramePointer, \ 1883 "Use the FP register for holding the frame pointer " \ 1884 "and not as a general purpose register.") \ 1885 \ 1886 product(size_t, AsyncLogBufferSize, 2*M, \ 1887 "Memory budget (in bytes) for the buffer of Asynchronous " \ 1888 "Logging (-Xlog:async).") \ 1889 range(100*K, 50*M) \ 1890 \ 1891 product(bool, CheckIntrinsics, true, DIAGNOSTIC, \ 1892 "When a class C is loaded, check that " \ 1893 "(1) all intrinsics defined by the VM for class C are present "\ 1894 "in the loaded class file and are marked with the " \ 1895 "@IntrinsicCandidate annotation, that " \ 1896 "(2) there is an intrinsic registered for all loaded methods " \ 1897 "that are annotated with the @IntrinsicCandidate annotation, " \ 1898 "and that " \ 1899 "(3) no orphan methods exist for class C (i.e., methods for " \ 1900 "which the VM declares an intrinsic but that are not declared "\ 1901 "in the loaded class C. " \ 1902 "Check (3) is available only in debug builds.") \ 1903 \ 1904 product_pd(intx, InitArrayShortSize, DIAGNOSTIC, \ 1905 "Threshold small size (in bytes) for clearing arrays. " \ 1906 "Anything this size or smaller may get converted to discrete " \ 1907 "scalar stores.") \ 1908 range(0, max_intx) \ 1909 constraint(InitArrayShortSizeConstraintFunc, AfterErgo) \ 1910 \ 1911 product(ccstr, AllocateHeapAt, nullptr, \ 1912 "Path to the directory where a temporary file will be created " \ 1913 "to use as the backing store for Java Heap.") \ 1914 \ 1915 product_pd(bool, VMContinuations, EXPERIMENTAL, \ 1916 "Enable VM continuations support") \ 1917 \ 1918 develop(bool, LoomDeoptAfterThaw, false, \ 1919 "Deopt stack after thaw") \ 1920 \ 1921 develop(bool, LoomVerifyAfterThaw, false, \ 1922 "Verify stack after thaw") \ 1923 \ 1924 develop(bool, VerifyContinuations, false, \ 1925 "Verify continuation consistency") \ 1926 \ 1927 develop(bool, UseContinuationFastPath, true, \ 1928 "Use fast-path frame walking in continuations") \ 1929 \ 1930 develop(int, VerifyMetaspaceInterval, DEBUG_ONLY(500) NOT_DEBUG(0), \ 1931 "Run periodic metaspace verifications (0 - none, " \ 1932 "1 - always, >1 every nth interval)") \ 1933 \ 1934 product(bool, ShowRegistersOnAssert, true, DIAGNOSTIC, \ 1935 "On internal errors, include registers in error report.") \ 1936 \ 1937 product(bool, UseSwitchProfiling, true, DIAGNOSTIC, \ 1938 "leverage profiling for table/lookup switch") \ 1939 \ 1940 develop(bool, TraceMemoryWriteback, false, \ 1941 "Trace memory writeback operations") \ 1942 \ 1943 JFR_ONLY(product(bool, FlightRecorder, false, \ 1944 "(Deprecated) Enable Flight Recorder")) \ 1945 \ 1946 JFR_ONLY(product(ccstr, FlightRecorderOptions, nullptr, \ 1947 "Flight Recorder options")) \ 1948 \ 1949 JFR_ONLY(product(ccstr, StartFlightRecording, nullptr, \ 1950 "Start flight recording with options")) \ 1951 \ 1952 product(bool, UseFastUnorderedTimeStamps, false, EXPERIMENTAL, \ 1953 "Use platform unstable time where supported for timestamps only") \ 1954 \ 1955 product(bool, UseEmptySlotsInSupers, true, \ 1956 "(Deprecated) Allow allocating fields in empty slots of " \ 1957 "super-classes") \ 1958 \ 1959 product(bool, DeoptimizeNMethodBarriersALot, false, DIAGNOSTIC, \ 1960 "Make nmethod barriers deoptimise a lot.") \ 1961 \ 1962 develop(bool, VerifyCrossModifyFence, \ 1963 false AARCH64_ONLY(DEBUG_ONLY(||true)), \ 1964 "Mark all threads after a safepoint, and clear on a modify " \ 1965 "fence. Add cleanliness checks.") \ 1966 \ 1967 product(int, LockingMode, LM_LIGHTWEIGHT, \ 1968 "Select locking mode: " \ 1969 "0: monitors only (LM_MONITOR), " \ 1970 "1: monitors & legacy stack-locking (LM_LEGACY), " \ 1971 "2: monitors & new lightweight locking (LM_LIGHTWEIGHT, default)") \ 1972 range(0, 2) \ 1973 \ 1974 product(bool, UseObjectMonitorTable, false, DIAGNOSTIC, \ 1975 "With Lightweight Locking mode, use a table to record inflated " \ 1976 "monitors rather than the first word of the object.") \ 1977 \ 1978 product(int, LightweightFastLockingSpins, 13, DIAGNOSTIC, \ 1979 "Specifies the number of time lightweight fast locking will " \ 1980 "attempt to CAS the markWord before inflating. Between each " \ 1981 "CAS it will spin for exponentially more time, resulting in " \ 1982 "a total number of spins on the order of O(2^value)") \ 1983 range(1, 30) \ 1984 \ 1985 product(uint, TrimNativeHeapInterval, 0, \ 1986 "Interval, in ms, at which the JVM will trim the native heap if " \ 1987 "the platform supports that. Lower values will reclaim memory " \ 1988 "more eagerly at the cost of higher overhead. A value of 0 " \ 1989 "(default) disables native heap trimming.") \ 1990 range(0, UINT_MAX) \ 1991 \ 1992 develop(bool, SimulateFullAddressSpace, false, \ 1993 "Simulates a very populated, fragmented address space; no " \ 1994 "targeted reservations will succeed.") \ 1995 \ 1996 product(bool, ProfileExceptionHandlers, true, \ 1997 "Profile exception handlers") \ 1998 \ 1999 product(bool, AlwaysRecordEvolDependencies, true, EXPERIMENTAL, \ 2000 "Unconditionally record nmethod dependencies on class " \ 2001 "rewriting/transformation independently of the JVMTI " \ 2002 "can_{retransform/redefine}_classes capabilities.") \ 2003 \ 2004 product(bool, UseSecondarySupersCache, true, DIAGNOSTIC, \ 2005 "Use secondary supers cache during subtype checks.") \ 2006 \ 2007 product(bool, UseSecondarySupersTable, false, DIAGNOSTIC, \ 2008 "Use hash table to lookup secondary supers.") \ 2009 \ 2010 product(bool, VerifySecondarySupers, false, DIAGNOSTIC, \ 2011 "Check that linear and hashed secondary lookups return the same result.") \ 2012 \ 2013 product(bool, StressSecondarySupers, false, DIAGNOSTIC, \ 2014 "Use a terrible hash function in order to generate many collisions.") \ 2015 2016 // end of RUNTIME_FLAGS 2017 2018 DECLARE_FLAGS(LP64_RUNTIME_FLAGS) 2019 DECLARE_ARCH_FLAGS(ARCH_FLAGS) 2020 DECLARE_FLAGS(RUNTIME_FLAGS) 2021 DECLARE_FLAGS(RUNTIME_OS_FLAGS) 2022 2023 #endif // SHARE_RUNTIME_GLOBALS_HPP --- EOF ---