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 /* Leyden */ \ 132 product(bool, UseCompatibleCompressedOops, false, \ 133 "Always use HeapBasedNarrowOop mode, so that AOT code can be " \ 134 "always work regardless of runtime heap range") \ 135 \ 136 product(int, ObjectAlignmentInBytes, 8, \ 137 "Default object alignment in bytes, 8 is minimum") \ 138 range(8, 256) \ 139 constraint(ObjectAlignmentInBytesConstraintFunc, AtParse) 140 141 #else 142 // !_LP64 143 144 #define LP64_RUNTIME_FLAGS(develop, \ 145 develop_pd, \ 146 product, \ 147 product_pd, \ 148 range, \ 149 constraint) 150 const bool UseCompressedOops = false; 151 const bool UseCompressedClassPointers = false; 152 const int ObjectAlignmentInBytes = 8; 153 154 #endif // _LP64 155 156 #define RUNTIME_FLAGS(develop, \ 157 develop_pd, \ 158 product, \ 159 product_pd, \ 160 range, \ 161 constraint) \ 162 \ 163 develop(bool, CheckCompressedOops, true, \ 164 "Generate checks in encoding/decoding code in debug VM") \ 165 \ 166 product(uintx, HeapSearchSteps, 3 PPC64_ONLY(+17), \ 167 "Heap allocation steps through preferred address regions to find" \ 168 " where it can allocate the heap. Number of steps to take per " \ 169 "region.") \ 170 range(1, max_uintx) \ 171 \ 172 product(uint, HandshakeTimeout, 0, DIAGNOSTIC, \ 173 "If nonzero set a timeout in milliseconds for handshakes") \ 174 \ 175 product(bool, AlwaysSafeConstructors, false, EXPERIMENTAL, \ 176 "Force safe construction, as if all fields are final.") \ 177 \ 178 product(bool, UnlockDiagnosticVMOptions, trueInDebug, DIAGNOSTIC, \ 179 "Enable normal processing of flags relating to field diagnostics")\ 180 \ 181 product(bool, UnlockExperimentalVMOptions, false, EXPERIMENTAL, \ 182 "Enable normal processing of flags relating to experimental " \ 183 "features") \ 184 \ 185 product(bool, JavaMonitorsInStackTrace, true, \ 186 "Print information about Java monitor locks when the stacks are " \ 187 "dumped") \ 188 \ 189 product_pd(bool, UseLargePages, \ 190 "Use large page memory") \ 191 \ 192 product_pd(bool, UseLargePagesIndividualAllocation, \ 193 "Allocate large pages individually for better affinity") \ 194 \ 195 develop(bool, LargePagesIndividualAllocationInjectError, false, \ 196 "Fail large pages individual allocation") \ 197 \ 198 product(bool, UseNUMA, false, \ 199 "Use NUMA if available") \ 200 \ 201 product(bool, UseNUMAInterleaving, false, \ 202 "Interleave memory across NUMA nodes if available") \ 203 \ 204 product(size_t, NUMAInterleaveGranularity, 2*M, \ 205 "Granularity to use for NUMA interleaving on Windows OS") \ 206 constraint(NUMAInterleaveGranularityConstraintFunc, AtParse) \ 207 \ 208 product(uintx, NUMAChunkResizeWeight, 20, \ 209 "Percentage (0-100) used to weight the current sample when " \ 210 "computing exponentially decaying average for " \ 211 "AdaptiveNUMAChunkSizing") \ 212 range(0, 100) \ 213 \ 214 product(size_t, NUMASpaceResizeRate, 1*G, \ 215 "Do not reallocate more than this amount per collection") \ 216 range(0, max_uintx) \ 217 \ 218 product(bool, UseAdaptiveNUMAChunkSizing, true, \ 219 "Enable adaptive chunk sizing for NUMA") \ 220 \ 221 product(bool, NUMAStats, false, \ 222 "Print NUMA stats in detailed heap information") \ 223 \ 224 product(bool, UseAES, false, \ 225 "Control whether AES instructions are used when available") \ 226 \ 227 product(bool, UseFMA, false, \ 228 "Control whether FMA instructions are used when available") \ 229 \ 230 product(bool, UseSHA, false, \ 231 "Control whether SHA instructions are used when available") \ 232 \ 233 product(bool, UseGHASHIntrinsics, false, DIAGNOSTIC, \ 234 "Use intrinsics for GHASH versions of crypto") \ 235 \ 236 product(bool, UseBASE64Intrinsics, false, \ 237 "Use intrinsics for java.util.Base64") \ 238 \ 239 product(bool, UsePoly1305Intrinsics, false, DIAGNOSTIC, \ 240 "Use intrinsics for sun.security.util.math.intpoly") \ 241 product(bool, UseIntPolyIntrinsics, false, DIAGNOSTIC, \ 242 "Use intrinsics for sun.security.util.math.intpoly.MontgomeryIntegerPolynomialP256") \ 243 \ 244 product(size_t, LargePageSizeInBytes, 0, \ 245 "Maximum large page size used (0 will use the default large " \ 246 "page size for the environment as the maximum)") \ 247 range(0, max_uintx) \ 248 \ 249 product(size_t, LargePageHeapSizeThreshold, 128*M, \ 250 "Use large pages if maximum heap is at least this big") \ 251 range(0, max_uintx) \ 252 \ 253 product(bool, ForceTimeHighResolution, false, \ 254 "Using high time resolution (for Win32 only)") \ 255 \ 256 develop(bool, TracePcPatching, false, \ 257 "Trace usage of frame::patch_pc") \ 258 \ 259 develop(bool, TraceRelocator, false, \ 260 "Trace the bytecode relocator") \ 261 \ 262 \ 263 product(bool, SafepointALot, false, DIAGNOSTIC, \ 264 "Generate a lot of safepoints. This works with " \ 265 "GuaranteedSafepointInterval") \ 266 \ 267 product(bool, HandshakeALot, false, DIAGNOSTIC, \ 268 "Generate a lot of handshakes. This works with " \ 269 "GuaranteedSafepointInterval") \ 270 \ 271 product_pd(bool, BackgroundCompilation, \ 272 "A thread requesting compilation is not blocked during " \ 273 "compilation") \ 274 \ 275 product(bool, MethodFlushing, true, \ 276 "Reclamation of compiled methods") \ 277 \ 278 develop(bool, VerifyStack, false, \ 279 "Verify stack of each thread when it is entering a runtime call") \ 280 \ 281 product(bool, ForceUnreachable, false, DIAGNOSTIC, \ 282 "Make all non code cache addresses to be unreachable by " \ 283 "forcing use of 64bit literal fixups") \ 284 \ 285 develop(bool, TraceDerivedPointers, false, \ 286 "Trace traversal of derived pointers on stack") \ 287 \ 288 develop(bool, TraceCodeBlobStacks, false, \ 289 "Trace stack-walk of codeblobs") \ 290 \ 291 develop(bool, PrintRewrites, false, \ 292 "Print methods that are being rewritten") \ 293 \ 294 product(bool, UseInlineCaches, true, \ 295 "Use Inline Caches for virtual calls ") \ 296 \ 297 product(size_t, InlineCacheBufferSize, 10*K, EXPERIMENTAL, \ 298 "InlineCacheBuffer size") \ 299 \ 300 product(bool, InlineArrayCopy, true, DIAGNOSTIC, \ 301 "Inline arraycopy native that is known to be part of " \ 302 "base library DLL") \ 303 \ 304 product(bool, InlineObjectHash, true, DIAGNOSTIC, \ 305 "Inline Object::hashCode() native that is known to be part " \ 306 "of base library DLL") \ 307 \ 308 product(bool, InlineNatives, true, DIAGNOSTIC, \ 309 "Inline natives that are known to be part of base library DLL") \ 310 \ 311 product(bool, InlineMathNatives, true, DIAGNOSTIC, \ 312 "Inline SinD, CosD, etc.") \ 313 \ 314 product(bool, InlineClassNatives, true, DIAGNOSTIC, \ 315 "Inline Class.isInstance, etc") \ 316 \ 317 product(bool, InlineThreadNatives, true, DIAGNOSTIC, \ 318 "Inline Thread.currentThread, etc") \ 319 \ 320 product(bool, InlineUnsafeOps, true, DIAGNOSTIC, \ 321 "Inline memory ops (native methods) from Unsafe") \ 322 \ 323 product(bool, UseAESIntrinsics, false, DIAGNOSTIC, \ 324 "Use intrinsics for AES versions of crypto") \ 325 \ 326 product(bool, UseAESCTRIntrinsics, false, DIAGNOSTIC, \ 327 "Use intrinsics for the paralleled version of AES/CTR crypto") \ 328 \ 329 product(bool, UseChaCha20Intrinsics, false, DIAGNOSTIC, \ 330 "Use intrinsics for the vectorized version of ChaCha20") \ 331 \ 332 product(bool, UseMD5Intrinsics, false, DIAGNOSTIC, \ 333 "Use intrinsics for MD5 crypto hash function") \ 334 \ 335 product(bool, UseSHA1Intrinsics, false, DIAGNOSTIC, \ 336 "Use intrinsics for SHA-1 crypto hash function. " \ 337 "Requires that UseSHA is enabled.") \ 338 \ 339 product(bool, UseSHA256Intrinsics, false, DIAGNOSTIC, \ 340 "Use intrinsics for SHA-224 and SHA-256 crypto hash functions. " \ 341 "Requires that UseSHA is enabled.") \ 342 \ 343 product(bool, UseSHA512Intrinsics, false, DIAGNOSTIC, \ 344 "Use intrinsics for SHA-384 and SHA-512 crypto hash functions. " \ 345 "Requires that UseSHA is enabled.") \ 346 \ 347 product(bool, UseSHA3Intrinsics, false, DIAGNOSTIC, \ 348 "Use intrinsics for SHA3 crypto hash function. " \ 349 "Requires that UseSHA is enabled.") \ 350 \ 351 product(bool, UseCRC32Intrinsics, false, DIAGNOSTIC, \ 352 "use intrinsics for java.util.zip.CRC32") \ 353 \ 354 product(bool, UseCRC32CIntrinsics, false, DIAGNOSTIC, \ 355 "use intrinsics for java.util.zip.CRC32C") \ 356 \ 357 product(bool, UseAdler32Intrinsics, false, DIAGNOSTIC, \ 358 "use intrinsics for java.util.zip.Adler32") \ 359 \ 360 product(bool, UseVectorizedMismatchIntrinsic, false, DIAGNOSTIC, \ 361 "Enables intrinsification of ArraysSupport.vectorizedMismatch()") \ 362 \ 363 product(bool, UseVectorizedHashCodeIntrinsic, false, DIAGNOSTIC, \ 364 "Enables intrinsification of ArraysSupport.vectorizedHashCode()") \ 365 \ 366 product(bool, UseCopySignIntrinsic, false, DIAGNOSTIC, \ 367 "Enables intrinsification of Math.copySign") \ 368 \ 369 product(bool, UseSignumIntrinsic, false, DIAGNOSTIC, \ 370 "Enables intrinsification of Math.signum") \ 371 \ 372 product_pd(bool, DelayCompilerStubsGeneration, DIAGNOSTIC, \ 373 "Use Compiler thread for compiler's stubs generation") \ 374 \ 375 product(ccstrlist, DisableIntrinsic, "", DIAGNOSTIC, \ 376 "do not expand intrinsics whose (internal) names appear here") \ 377 constraint(DisableIntrinsicConstraintFunc,AfterErgo) \ 378 \ 379 product(ccstrlist, ControlIntrinsic, "", DIAGNOSTIC, \ 380 "Control intrinsics using a list of +/- (internal) names, " \ 381 "separated by commas") \ 382 constraint(ControlIntrinsicConstraintFunc,AfterErgo) \ 383 \ 384 develop(bool, TraceCallFixup, false, \ 385 "Trace all call fixups") \ 386 \ 387 develop(bool, DeoptimizeALot, false, \ 388 "Deoptimize at every exit from the runtime system") \ 389 \ 390 develop(ccstrlist, DeoptimizeOnlyAt, "", \ 391 "A comma separated list of bcis to deoptimize at") \ 392 \ 393 develop(bool, DeoptimizeRandom, false, \ 394 "Deoptimize random frames on random exit from the runtime system")\ 395 \ 396 develop(bool, ZombieALot, false, \ 397 "Create non-entrant nmethods at exit from the runtime system") \ 398 \ 399 develop(bool, WalkStackALot, false, \ 400 "Trace stack (no print) at every exit from the runtime system") \ 401 \ 402 develop(bool, DeoptimizeObjectsALot, false, \ 403 "For testing purposes concurrent threads revert optimizations " \ 404 "based on escape analysis at intervals given with " \ 405 "DeoptimizeObjectsALotInterval=n. The thread count is given " \ 406 "with DeoptimizeObjectsALotThreadCountSingle and " \ 407 "DeoptimizeObjectsALotThreadCountAll.") \ 408 \ 409 develop(uint64_t, DeoptimizeObjectsALotInterval, 5, \ 410 "Interval for DeoptimizeObjectsALot.") \ 411 range(0, max_jlong) \ 412 \ 413 develop(int, DeoptimizeObjectsALotThreadCountSingle, 1, \ 414 "The number of threads that revert optimizations based on " \ 415 "escape analysis for a single thread if DeoptimizeObjectsALot " \ 416 "is enabled. The target thread is selected round robin." ) \ 417 range(0, max_jint) \ 418 \ 419 develop(int, DeoptimizeObjectsALotThreadCountAll, 1, \ 420 "The number of threads that revert optimizations based on " \ 421 "escape analysis for all threads if DeoptimizeObjectsALot " \ 422 "is enabled." ) \ 423 range(0, max_jint) \ 424 \ 425 develop(bool, VerifyLastFrame, false, \ 426 "Verify oops on last frame on entry to VM") \ 427 \ 428 product(bool, SafepointTimeout, false, \ 429 "Time out and warn or fail after SafepointTimeoutDelay " \ 430 "milliseconds if failed to reach safepoint") \ 431 \ 432 product(bool, AbortVMOnSafepointTimeout, false, DIAGNOSTIC, \ 433 "Abort upon failure to reach safepoint (see SafepointTimeout)") \ 434 \ 435 product(uint64_t, AbortVMOnSafepointTimeoutDelay, 0, DIAGNOSTIC, \ 436 "Delay in milliseconds for option AbortVMOnSafepointTimeout") \ 437 range(0, max_jlong) \ 438 \ 439 product(bool, AbortVMOnVMOperationTimeout, false, DIAGNOSTIC, \ 440 "Abort upon failure to complete VM operation promptly") \ 441 \ 442 product(intx, AbortVMOnVMOperationTimeoutDelay, 1000, DIAGNOSTIC, \ 443 "Delay in milliseconds for option AbortVMOnVMOperationTimeout") \ 444 range(0, max_intx) \ 445 \ 446 product(bool, MaxFDLimit, true, \ 447 "Bump the number of file descriptors to maximum (Unix only)") \ 448 \ 449 product(bool, LogEvents, true, DIAGNOSTIC, \ 450 "Enable the various ring buffer event logs") \ 451 \ 452 product(int, LogEventsBufferEntries, 20, DIAGNOSTIC, \ 453 "Number of ring buffer event logs") \ 454 range(1, NOT_LP64(1*K) LP64_ONLY(1*M)) \ 455 \ 456 product(bool, BytecodeVerificationRemote, true, DIAGNOSTIC, \ 457 "Enable the Java bytecode verifier for remote classes") \ 458 \ 459 product(bool, BytecodeVerificationLocal, false, DIAGNOSTIC, \ 460 "Enable the Java bytecode verifier for local classes") \ 461 \ 462 develop(bool, VerifyStackAtCalls, false, \ 463 "Verify that the stack pointer is unchanged after calls") \ 464 \ 465 develop(bool, TraceJavaAssertions, false, \ 466 "Trace java language assertions") \ 467 \ 468 develop(bool, VerifyCodeCache, false, \ 469 "Verify code cache on memory allocation/deallocation") \ 470 \ 471 develop(bool, ZapResourceArea, trueInDebug, \ 472 "Zap freed resource/arena space") \ 473 \ 474 develop(bool, ZapVMHandleArea, trueInDebug, \ 475 "Zap freed VM handle space") \ 476 \ 477 develop(bool, ZapStackSegments, trueInDebug, \ 478 "Zap allocated/freed stack segments") \ 479 \ 480 develop(bool, ZapUnusedHeapArea, trueInDebug, \ 481 "Zap unused heap space") \ 482 \ 483 develop(bool, ZapFillerObjects, trueInDebug, \ 484 "Zap filler objects") \ 485 \ 486 develop(bool, ZapTLAB, trueInDebug, \ 487 "Zap allocated TLABs") \ 488 \ 489 product(bool, ExecutingUnitTests, false, \ 490 "Whether the JVM is running unit tests or not") \ 491 \ 492 develop(uint, ErrorHandlerTest, 0, \ 493 "If > 0, provokes an error after VM initialization; the value " \ 494 "determines which error to provoke. See controlled_crash() " \ 495 "in vmError.cpp.") \ 496 range(0, 17) \ 497 \ 498 develop(uint, TestCrashInErrorHandler, 0, \ 499 "If > 0, provokes an error inside VM error handler (a secondary " \ 500 "crash). see controlled_crash() in vmError.cpp") \ 501 range(0, 17) \ 502 \ 503 develop(bool, TestSafeFetchInErrorHandler, false , \ 504 "If true, tests SafeFetch inside error handler.") \ 505 \ 506 develop(bool, TestUnresponsiveErrorHandler, false, \ 507 "If true, simulates an unresponsive error handler.") \ 508 \ 509 develop(bool, Verbose, false, \ 510 "Print additional debugging information from other modes") \ 511 \ 512 develop(bool, PrintMiscellaneous, false, \ 513 "Print uncategorized debugging information (requires +Verbose)") \ 514 \ 515 develop(bool, WizardMode, false, \ 516 "Print much more debugging information") \ 517 \ 518 product(bool, ShowMessageBoxOnError, false, \ 519 "Keep process alive on VM fatal error") \ 520 \ 521 product(bool, CreateCoredumpOnCrash, true, \ 522 "Create core/mini dump on VM fatal error") \ 523 \ 524 product(uint64_t, ErrorLogTimeout, 2 * 60, \ 525 "Timeout, in seconds, to limit the time spent on writing an " \ 526 "error log in case of a crash.") \ 527 range(0, (uint64_t)max_jlong/1000) \ 528 \ 529 product(bool, ErrorLogSecondaryErrorDetails, false, DIAGNOSTIC, \ 530 "If enabled, show details on secondary crashes in the error log") \ 531 \ 532 develop(intx, TraceDwarfLevel, 0, \ 533 "Debug levels for the dwarf parser") \ 534 range(0, 4) \ 535 \ 536 product(bool, SuppressFatalErrorMessage, false, \ 537 "Report NO fatal error message (avoid deadlock)") \ 538 \ 539 product(ccstrlist, OnError, "", \ 540 "Run user-defined commands on fatal error; see VMError.cpp " \ 541 "for examples") \ 542 \ 543 product(ccstrlist, OnOutOfMemoryError, "", \ 544 "Run user-defined commands on first java.lang.OutOfMemoryError " \ 545 "thrown from JVM") \ 546 \ 547 product(bool, HeapDumpBeforeFullGC, false, MANAGEABLE, \ 548 "Dump heap to file before any major stop-the-world GC " \ 549 "(also see FullGCHeapDumpLimit, HeapDumpPath, HeapDumpGzipLevel)")\ 550 \ 551 product(bool, HeapDumpAfterFullGC, false, MANAGEABLE, \ 552 "Dump heap to file after any major stop-the-world GC " \ 553 "(also see FullGCHeapDumpLimit, HeapDumpPath, HeapDumpGzipLevel)")\ 554 \ 555 product(uint, FullGCHeapDumpLimit, 0, MANAGEABLE, \ 556 "Limit the number of heap dumps triggered by " \ 557 "HeapDumpBeforeFullGC or HeapDumpAfterFullGC " \ 558 "(0 means no limit)") \ 559 \ 560 product(bool, HeapDumpOnOutOfMemoryError, false, MANAGEABLE, \ 561 "Dump heap to file when java.lang.OutOfMemoryError is thrown " \ 562 "from JVM " \ 563 "(also see HeapDumpPath, HeapDumpGzipLevel)") \ 564 \ 565 product(ccstr, HeapDumpPath, nullptr, MANAGEABLE, \ 566 "When HeapDumpOnOutOfMemoryError, HeapDumpBeforeFullGC " \ 567 "or HeapDumpAfterFullGC is on, the path (filename or " \ 568 "directory) of the dump file (defaults to java_pid<pid>.hprof " \ 569 "in the working directory)") \ 570 \ 571 product(int, HeapDumpGzipLevel, 0, MANAGEABLE, \ 572 "When HeapDumpOnOutOfMemoryError, HeapDumpBeforeFullGC " \ 573 "or HeapDumpAfterFullGC is on, the gzip compression " \ 574 "level of the dump file. 0 (the default) disables gzip " \ 575 "compression. Otherwise the level must be between 1 and 9.") \ 576 range(0, 9) \ 577 \ 578 product(ccstr, NativeMemoryTracking, DEBUG_ONLY("summary") NOT_DEBUG("off"), \ 579 "Native memory tracking options") \ 580 \ 581 product(bool, PrintNMTStatistics, false, DIAGNOSTIC, \ 582 "Print native memory tracking summary data if it is on") \ 583 \ 584 product(bool, LogCompilation, false, DIAGNOSTIC, \ 585 "Log compilation activity in detail to LogFile") \ 586 \ 587 product(bool, PrintCompilation, false, \ 588 "Print compilations") \ 589 \ 590 product(intx, RepeatCompilation, 0, DIAGNOSTIC, \ 591 "Repeat compilation without installing code (number of times)") \ 592 range(0, max_jint) \ 593 \ 594 product(bool, PrintExtendedThreadInfo, false, \ 595 "Print more information in thread dump") \ 596 \ 597 product(intx, ScavengeRootsInCode, 2, DIAGNOSTIC, \ 598 "0: do not allow scavengable oops in the code cache; " \ 599 "1: allow scavenging from the code cache; " \ 600 "2: emit as many constants as the compiler can see") \ 601 range(0, 2) \ 602 \ 603 product(bool, AlwaysRestoreFPU, false, \ 604 "Restore the FPU control word after every JNI call (expensive)") \ 605 \ 606 product(bool, PrintCompilation2, false, DIAGNOSTIC, \ 607 "Print additional statistics per compilation") \ 608 \ 609 product(bool, PrintAdapterHandlers, false, DIAGNOSTIC, \ 610 "Print code generated for i2c/c2i adapters") \ 611 \ 612 product(bool, VerifyAdapterCalls, trueInDebug, DIAGNOSTIC, \ 613 "Verify that i2c/c2i adapters are called properly") \ 614 \ 615 develop(bool, VerifyAdapterSharing, false, \ 616 "Verify that the code for shared adapters is the equivalent") \ 617 \ 618 product(bool, PrintAssembly, false, DIAGNOSTIC, \ 619 "Print assembly code (using external disassembler.so)") \ 620 \ 621 product(ccstr, PrintAssemblyOptions, nullptr, DIAGNOSTIC, \ 622 "Print options string passed to disassembler.so") \ 623 \ 624 develop(bool, PrintNMethodStatistics, false, \ 625 "Print a summary statistic for the generated nmethods") \ 626 \ 627 product(bool, PrintNMethods, false, DIAGNOSTIC, \ 628 "Print assembly code for nmethods when generated") \ 629 \ 630 product(bool, PrintNativeNMethods, false, DIAGNOSTIC, \ 631 "Print assembly code for native nmethods when generated") \ 632 \ 633 develop(bool, PrintDebugInfo, false, \ 634 "Print debug information for all nmethods when generated") \ 635 \ 636 develop(bool, PrintRelocations, false, \ 637 "Print relocation information for all nmethods when generated") \ 638 \ 639 develop(bool, PrintDependencies, false, \ 640 "Print dependency information for all nmethods when generated") \ 641 \ 642 develop(bool, PrintExceptionHandlers, false, \ 643 "Print exception handler tables for all nmethods when generated") \ 644 \ 645 develop(bool, StressCompiledExceptionHandlers, false, \ 646 "Exercise compiled exception handlers") \ 647 \ 648 develop(bool, InterceptOSException, false, \ 649 "Start debugger when an implicit OS (e.g. null pointer) " \ 650 "exception happens") \ 651 \ 652 product(bool, PrintCodeCache, false, \ 653 "Print the code cache memory usage when exiting") \ 654 \ 655 develop(bool, PrintCodeCache2, false, \ 656 "Print detailed usage information on the code cache when exiting")\ 657 \ 658 product(bool, PrintCodeCacheOnCompilation, false, \ 659 "Print the code cache memory usage each time a method is " \ 660 "compiled") \ 661 \ 662 product(bool, PrintCodeHeapAnalytics, false, DIAGNOSTIC, \ 663 "Print code heap usage statistics on exit and on full condition") \ 664 \ 665 product(bool, PrintStubCode, false, DIAGNOSTIC, \ 666 "Print generated stub code") \ 667 \ 668 product(bool, StackTraceInThrowable, true, \ 669 "Collect backtrace in throwable when exception happens") \ 670 \ 671 product(bool, OmitStackTraceInFastThrow, true, \ 672 "Omit backtraces for some 'hot' exceptions in optimized code") \ 673 \ 674 product(bool, ShowCodeDetailsInExceptionMessages, true, MANAGEABLE, \ 675 "Show exception messages from RuntimeExceptions that contain " \ 676 "snippets of the failing code. Disable this to improve privacy.") \ 677 \ 678 product(bool, PrintWarnings, true, \ 679 "Print JVM warnings to output stream") \ 680 \ 681 develop(bool, RegisterReferences, true, \ 682 "Tell whether the VM should register soft/weak/final/phantom " \ 683 "references") \ 684 \ 685 develop(bool, PrintCodeCacheExtension, false, \ 686 "Print extension of code cache") \ 687 \ 688 develop(bool, UsePrivilegedStack, true, \ 689 "Enable the security JVM functions") \ 690 \ 691 product(bool, ClassUnloading, true, \ 692 "Do unloading of classes") \ 693 \ 694 product(bool, ClassUnloadingWithConcurrentMark, true, \ 695 "Do unloading of classes with a concurrent marking cycle") \ 696 \ 697 develop(bool, PrintSystemDictionaryAtExit, false, \ 698 "Print the system dictionary at exit") \ 699 \ 700 develop(bool, PrintClassLoaderDataGraphAtExit, false, \ 701 "Print the class loader data graph at exit") \ 702 \ 703 product(bool, AllowParallelDefineClass, false, \ 704 "Allow parallel defineClass requests for class loaders " \ 705 "registering as parallel capable") \ 706 \ 707 product_pd(bool, DontYieldALot, \ 708 "(Deprecated) Throw away obvious excess yield calls") \ 709 \ 710 product(bool, DisablePrimordialThreadGuardPages, false, EXPERIMENTAL, \ 711 "Disable the use of stack guard pages if the JVM is loaded " \ 712 "on the primordial process thread") \ 713 \ 714 product(bool, DoJVMTIVirtualThreadTransitions, true, EXPERIMENTAL, \ 715 "Do JVMTI virtual thread mount/unmount transitions " \ 716 "(disabling this flag implies no JVMTI events are posted)") \ 717 \ 718 /* notice: the max range value here is max_jint, not max_intx */ \ 719 /* because of overflow issue */ \ 720 product(intx, AsyncDeflationInterval, 250, DIAGNOSTIC, \ 721 "Async deflate idle monitors every so many milliseconds when " \ 722 "MonitorUsedDeflationThreshold is exceeded (0 is off).") \ 723 range(0, max_jint) \ 724 \ 725 /* notice: the max range value here is max_jint, not max_intx */ \ 726 /* because of overflow issue */ \ 727 product(intx, GuaranteedAsyncDeflationInterval, 60000, DIAGNOSTIC, \ 728 "Async deflate idle monitors every so many milliseconds even " \ 729 "when MonitorUsedDeflationThreshold is NOT exceeded (0 is off).") \ 730 range(0, max_jint) \ 731 \ 732 product(size_t, AvgMonitorsPerThreadEstimate, 1024, DIAGNOSTIC, \ 733 "Used to estimate a variable ceiling based on number of threads " \ 734 "for use with MonitorUsedDeflationThreshold (0 is off).") \ 735 range(0, max_uintx) \ 736 \ 737 /* notice: the max range value here is max_jint, not max_intx */ \ 738 /* because of overflow issue */ \ 739 product(intx, MonitorDeflationMax, 1000000, DIAGNOSTIC, \ 740 "The maximum number of monitors to deflate, unlink and delete " \ 741 "at one time (minimum is 1024).") \ 742 range(1024, max_jint) \ 743 \ 744 product(intx, MonitorUnlinkBatch, 500, DIAGNOSTIC, \ 745 "The maximum number of monitors to unlink in one batch. ") \ 746 range(1, max_jint) \ 747 \ 748 product(int, MonitorUsedDeflationThreshold, 90, DIAGNOSTIC, \ 749 "Percentage of used monitors before triggering deflation (0 is " \ 750 "off). The check is performed on AsyncDeflationInterval or " \ 751 "GuaranteedAsyncDeflationInterval, whichever is lower.") \ 752 range(0, 100) \ 753 \ 754 product(uintx, NoAsyncDeflationProgressMax, 3, DIAGNOSTIC, \ 755 "Max number of no progress async deflation attempts to tolerate " \ 756 "before adjusting the in_use_list_ceiling up (0 is off).") \ 757 range(0, max_uintx) \ 758 \ 759 product(intx, hashCode, 5, EXPERIMENTAL, \ 760 "(Unstable) select hashCode generation algorithm") \ 761 \ 762 product(bool, ReduceSignalUsage, false, \ 763 "Reduce the use of OS signals in Java and/or the VM") \ 764 \ 765 develop(bool, LoadLineNumberTables, true, \ 766 "Tell whether the class file parser loads line number tables") \ 767 \ 768 develop(bool, LoadLocalVariableTables, true, \ 769 "Tell whether the class file parser loads local variable tables") \ 770 \ 771 develop(bool, LoadLocalVariableTypeTables, true, \ 772 "Tell whether the class file parser loads local variable type" \ 773 "tables") \ 774 \ 775 product(bool, AllowUserSignalHandlers, false, \ 776 "Application will install primary signal handlers for the JVM " \ 777 "(Unix only)") \ 778 \ 779 product(bool, UseSignalChaining, true, \ 780 "Use signal-chaining to invoke signal handlers installed " \ 781 "by the application (Unix only)") \ 782 \ 783 product(bool, RestoreMXCSROnJNICalls, false, \ 784 "Restore MXCSR when returning from JNI calls") \ 785 \ 786 product(bool, CheckJNICalls, false, \ 787 "Verify all arguments to JNI calls") \ 788 \ 789 product(bool, UseFastJNIAccessors, true, \ 790 "Use optimized versions of Get<Primitive>Field") \ 791 \ 792 product(intx, MaxJNILocalCapacity, 65536, \ 793 "Maximum allowable local JNI handle capacity to " \ 794 "EnsureLocalCapacity() and PushLocalFrame(), " \ 795 "where <= 0 is unlimited, default: 65536") \ 796 range(min_intx, max_intx) \ 797 \ 798 product(bool, EagerXrunInit, false, \ 799 "Eagerly initialize -Xrun libraries; allows startup profiling, " \ 800 "but not all -Xrun libraries may support the state of the VM " \ 801 "at this time") \ 802 \ 803 product(bool, PreserveAllAnnotations, false, \ 804 "(Deprecated) Preserve RuntimeInvisibleAnnotations as well " \ 805 "as RuntimeVisibleAnnotations") \ 806 \ 807 develop(uintx, PreallocatedOutOfMemoryErrorCount, 4, \ 808 "Number of OutOfMemoryErrors preallocated with backtrace") \ 809 \ 810 product(bool, UseXMMForArrayCopy, false, \ 811 "Use SSE2 MOVQ instruction for Arraycopy") \ 812 \ 813 develop(bool, PrintFieldLayout, false, \ 814 "Print field layout for each class") \ 815 \ 816 /* Need to limit the extent of the padding to reasonable size. */\ 817 /* 8K is well beyond the reasonable HW cache line size, even with */\ 818 /* aggressive prefetching, while still leaving the room for segregating */\ 819 /* among the distinct pages. */\ 820 product(int, ContendedPaddingWidth, 128, \ 821 "How many bytes to pad the fields/classes marked @Contended with")\ 822 range(0, 8192) \ 823 constraint(ContendedPaddingWidthConstraintFunc,AfterErgo) \ 824 \ 825 product(bool, EnableContended, true, \ 826 "Enable @Contended annotation support") \ 827 \ 828 product(bool, RestrictContended, true, \ 829 "Restrict @Contended to trusted classes") \ 830 \ 831 product(int, DiagnoseSyncOnValueBasedClasses, 0, DIAGNOSTIC, \ 832 "Detect and take action upon identifying synchronization on " \ 833 "value based classes. Modes: " \ 834 "0: off; " \ 835 "1: exit with fatal error; " \ 836 "2: log message to stdout. Output file can be specified with " \ 837 " -Xlog:valuebasedclasses. If JFR is running it will " \ 838 " also generate JFR events.") \ 839 range(0, 2) \ 840 \ 841 product(bool, ExitOnOutOfMemoryError, false, \ 842 "JVM exits on the first occurrence of an out-of-memory error " \ 843 "thrown from JVM") \ 844 \ 845 product(bool, CrashOnOutOfMemoryError, false, \ 846 "JVM aborts, producing an error log and core/mini dump, on the " \ 847 "first occurrence of an out-of-memory error thrown from JVM") \ 848 \ 849 product(intx, UserThreadWaitAttemptsAtExit, 30, \ 850 "The number of times to wait for user threads to stop executing " \ 851 "native code during JVM exit. Each wait lasts 10 milliseconds. " \ 852 "The maximum number of waits is 1000, to wait at most 10 " \ 853 "seconds.") \ 854 range(0, 1000) \ 855 \ 856 /* tracing */ \ 857 \ 858 develop(bool, StressRewriter, false, \ 859 "Stress linktime bytecode rewriting") \ 860 \ 861 product(ccstr, TraceJVMTI, nullptr, \ 862 "Trace flags for JVMTI functions and events") \ 863 \ 864 product(bool, StressLdcRewrite, false, DIAGNOSTIC, \ 865 "Force ldc -> ldc_w rewrite during RedefineClasses. " \ 866 "This option can change an EMCP method into an obsolete method " \ 867 "and can affect tests that expect specific methods to be EMCP. " \ 868 "This option should be used with caution.") \ 869 \ 870 product(bool, AllowRedefinitionToAddDeleteMethods, false, \ 871 "(Deprecated) Allow redefinition to add and delete private " \ 872 "static or final methods for compatibility with old releases") \ 873 \ 874 develop(bool, TraceBytecodes, false, \ 875 "Trace bytecode execution") \ 876 \ 877 develop(bool, TraceBytecodesTruncated, false, \ 878 "Truncate non control-flow bytecode when tracing bytecode") \ 879 \ 880 develop(bool, VerifyDependencies, trueInDebug, \ 881 "Exercise and verify the compilation dependency mechanism") \ 882 \ 883 develop(bool, TraceNewOopMapGeneration, false, \ 884 "Trace OopMapGeneration") \ 885 \ 886 develop(bool, TraceNewOopMapGenerationDetailed, false, \ 887 "Trace OopMapGeneration: print detailed cell states") \ 888 \ 889 develop(bool, TimeOopMap, false, \ 890 "Time calls to GenerateOopMap::compute_map() in sum") \ 891 \ 892 develop(bool, TimeOopMap2, false, \ 893 "Time calls to GenerateOopMap::compute_map() individually") \ 894 \ 895 develop(bool, TraceOopMapRewrites, false, \ 896 "Trace rewriting of methods during oop map generation") \ 897 \ 898 develop(bool, TraceFinalizerRegistration, false, \ 899 "Trace registration of final references") \ 900 \ 901 product(bool, IgnoreEmptyClassPaths, false, \ 902 "Ignore empty path elements in -classpath") \ 903 \ 904 product(bool, PrintHeapAtSIGBREAK, true, \ 905 "Print heap layout in response to SIGBREAK") \ 906 \ 907 product(bool, PrintClassHistogram, false, MANAGEABLE, \ 908 "Print a histogram of class instances") \ 909 \ 910 product(double, ObjectCountCutOffPercent, 0.5, EXPERIMENTAL, \ 911 "The percentage of the used heap that the instances of a class " \ 912 "must occupy for the class to generate a trace event") \ 913 range(0.0, 100.0) \ 914 \ 915 /* JVMTI heap profiling */ \ 916 \ 917 product(bool, VerifyBeforeIteration, false, DIAGNOSTIC, \ 918 "Verify memory system before JVMTI iteration") \ 919 \ 920 /* compiler */ \ 921 \ 922 /* notice: the max range value here is max_jint, not max_intx */ \ 923 /* because of overflow issue */ \ 924 product(intx, CICompilerCount, CI_COMPILER_COUNT, \ 925 "Number of compiler threads to run") \ 926 range(0, max_jint) \ 927 constraint(CICompilerCountConstraintFunc, AfterErgo) \ 928 \ 929 product(bool, UseDynamicNumberOfCompilerThreads, true, \ 930 "Dynamically choose the number of parallel compiler threads") \ 931 \ 932 product(bool, ReduceNumberOfCompilerThreads, true, DIAGNOSTIC, \ 933 "Reduce the number of parallel compiler threads when they " \ 934 "are not used") \ 935 \ 936 product(bool, TraceCompilerThreads, false, DIAGNOSTIC, \ 937 "Trace creation and removal of compiler threads") \ 938 \ 939 product(ccstr, LogClassLoadingCauseFor, nullptr, \ 940 "Apply -Xlog:class+load+cause* to classes whose fully " \ 941 "qualified name contains this string (\"*\" matches " \ 942 "any class).") \ 943 \ 944 develop(bool, InjectCompilerCreationFailure, false, \ 945 "Inject thread creation failures for " \ 946 "UseDynamicNumberOfCompilerThreads") \ 947 \ 948 develop(bool, GenerateSynchronizationCode, true, \ 949 "generate locking/unlocking code for synchronized methods and " \ 950 "monitors") \ 951 \ 952 product_pd(bool, ImplicitNullChecks, DIAGNOSTIC, \ 953 "Generate code for implicit null checks") \ 954 \ 955 product_pd(bool, TrapBasedNullChecks, \ 956 "Generate code for null checks that uses a cmp and trap " \ 957 "instruction raising SIGTRAP. This is only used if an access to" \ 958 "null (+offset) will not raise a SIGSEGV, i.e.," \ 959 "ImplicitNullChecks don't work (PPC64).") \ 960 \ 961 product(bool, EnableThreadSMRStatistics, trueInDebug, DIAGNOSTIC, \ 962 "Enable Thread SMR Statistics") \ 963 \ 964 product(bool, UseNotificationThread, true, \ 965 "(Deprecated) Use Notification Thread") \ 966 \ 967 product(bool, Inline, true, \ 968 "Enable inlining") \ 969 \ 970 product(bool, ClipInlining, true, \ 971 "Clip inlining if aggregate method exceeds DesiredMethodLimit") \ 972 \ 973 develop(bool, UseCHA, true, \ 974 "Enable CHA") \ 975 \ 976 product(bool, UseTypeProfile, true, \ 977 "Check interpreter profile for historically monomorphic calls") \ 978 \ 979 product(bool, PrintInlining, false, DIAGNOSTIC, \ 980 "Print inlining optimizations") \ 981 \ 982 product(bool, UsePopCountInstruction, false, \ 983 "Use population count instruction") \ 984 \ 985 develop(bool, TraceMethodReplacement, false, \ 986 "Print when methods are replaced do to recompilation") \ 987 \ 988 product(intx, MinPassesBeforeFlush, 10, DIAGNOSTIC, \ 989 "Minimum number of sweeper passes before an nmethod " \ 990 "can be flushed") \ 991 range(0, max_intx) \ 992 \ 993 develop(bool, StressCodeBuffers, false, \ 994 "Exercise code buffer expansion and other rare state changes") \ 995 \ 996 product(bool, DebugNonSafepoints, trueInDebug, DIAGNOSTIC, \ 997 "Generate extra debugging information for non-safepoints in " \ 998 "nmethods") \ 999 \ 1000 product(bool, PrintVMOptions, false, \ 1001 "Print flags that appeared on the command line") \ 1002 \ 1003 product(bool, IgnoreUnrecognizedVMOptions, false, \ 1004 "Ignore unrecognized VM options") \ 1005 \ 1006 product(bool, PrintCommandLineFlags, false, \ 1007 "Print flags specified on command line or set by ergonomics") \ 1008 \ 1009 product(bool, PrintFlagsInitial, false, \ 1010 "Print all VM flags before argument processing and exit VM") \ 1011 \ 1012 product(bool, PrintFlagsFinal, false, \ 1013 "Print all VM flags after argument and ergonomic processing") \ 1014 \ 1015 develop(bool, PrintFlagsWithComments, false, \ 1016 "Print all VM flags with default values and descriptions and " \ 1017 "exit") \ 1018 \ 1019 product(bool, PrintFlagsRanges, false, \ 1020 "Print VM flags and their ranges") \ 1021 \ 1022 product(bool, SerializeVMOutput, true, DIAGNOSTIC, \ 1023 "Use a mutex to serialize output to tty and LogFile") \ 1024 \ 1025 product(bool, DisplayVMOutput, true, DIAGNOSTIC, \ 1026 "Display all VM output on the tty, independently of LogVMOutput") \ 1027 \ 1028 product(bool, LogVMOutput, false, DIAGNOSTIC, \ 1029 "Save VM output to LogFile") \ 1030 \ 1031 product(ccstr, LogFile, nullptr, DIAGNOSTIC, \ 1032 "If LogVMOutput or LogCompilation is on, save VM output to " \ 1033 "this file [default: ./hotspot_%p.log] (%p replaced with pidNNN)")\ 1034 \ 1035 product(ccstr, ErrorFile, nullptr, \ 1036 "If an error occurs, save the error data to this file " \ 1037 "[default: ./hs_err_%p.log] (%p replaced with pidNNN)") \ 1038 \ 1039 product(bool, ExtensiveErrorReports, \ 1040 PRODUCT_ONLY(false) NOT_PRODUCT(true), \ 1041 "Error reports are more extensive.") \ 1042 \ 1043 product(bool, DisplayVMOutputToStderr, false, \ 1044 "If DisplayVMOutput is true, display all VM output to stderr") \ 1045 \ 1046 product(bool, DisplayVMOutputToStdout, false, \ 1047 "If DisplayVMOutput is true, display all VM output to stdout") \ 1048 \ 1049 product(bool, ErrorFileToStderr, false, \ 1050 "If true, error data is printed to stderr instead of a file") \ 1051 \ 1052 product(bool, ErrorFileToStdout, false, \ 1053 "If true, error data is printed to stdout instead of a file") \ 1054 \ 1055 develop(bool, VerifyHeavyMonitors, false, \ 1056 "Checks that no stack locking happens when using " \ 1057 "-XX:LockingMode=0 (LM_MONITOR)") \ 1058 \ 1059 product(bool, PrintStringTableStatistics, false, \ 1060 "print statistics about the StringTable and SymbolTable") \ 1061 \ 1062 product(bool, VerifyStringTableAtExit, false, DIAGNOSTIC, \ 1063 "verify StringTable contents at exit") \ 1064 \ 1065 develop(bool, PrintSymbolTableSizeHistogram, false, \ 1066 "print histogram of the symbol table") \ 1067 \ 1068 product(ccstr, AbortVMOnException, nullptr, DIAGNOSTIC, \ 1069 "Call fatal if this exception is thrown. Example: " \ 1070 "java -XX:AbortVMOnException=java.lang.NullPointerException Foo") \ 1071 \ 1072 product(ccstr, AbortVMOnExceptionMessage, nullptr, DIAGNOSTIC, \ 1073 "Call fatal if the exception pointed by AbortVMOnException " \ 1074 "has this message") \ 1075 \ 1076 develop(bool, DebugVtables, false, \ 1077 "add debugging code to vtable dispatch") \ 1078 \ 1079 product(bool, RangeCheckElimination, true, \ 1080 "Eliminate range checks") \ 1081 \ 1082 develop_pd(bool, UncommonNullCast, \ 1083 "track occurrences of null in casts; adjust compiler tactics") \ 1084 \ 1085 develop(bool, TypeProfileCasts, true, \ 1086 "treat casts like calls for purposes of type profiling") \ 1087 \ 1088 develop(bool, TraceLivenessGen, false, \ 1089 "Trace the generation of liveness analysis information") \ 1090 \ 1091 develop(bool, TraceLivenessQuery, false, \ 1092 "Trace queries of liveness analysis information") \ 1093 \ 1094 develop(bool, CollectIndexSetStatistics, false, \ 1095 "Collect information about IndexSets") \ 1096 \ 1097 develop(int, FastAllocateSizeLimit, 128*K, \ 1098 /* Note: This value is zero mod 1<<13 for a cheap sparc set. */ \ 1099 "Inline allocations larger than this in doublewords must go slow")\ 1100 \ 1101 product_pd(bool, CompactStrings, \ 1102 "Enable Strings to use single byte chars in backing store") \ 1103 \ 1104 product_pd(uint, TypeProfileLevel, \ 1105 "=XYZ, with Z: Type profiling of arguments at call; " \ 1106 "Y: Type profiling of return value at call; " \ 1107 "X: Type profiling of parameters to methods; " \ 1108 "X, Y and Z in 0=off ; 1=jsr292 only; 2=all methods") \ 1109 constraint(TypeProfileLevelConstraintFunc, AfterErgo) \ 1110 \ 1111 product(int, TypeProfileArgsLimit, 2, \ 1112 "max number of call arguments to consider for type profiling") \ 1113 range(0, 16) \ 1114 \ 1115 product(int, TypeProfileParmsLimit, 2, \ 1116 "max number of incoming parameters to consider for type profiling"\ 1117 ", -1 for all") \ 1118 range(-1, 64) \ 1119 \ 1120 /* statistics */ \ 1121 develop(bool, CountCompiledCalls, false, \ 1122 "Count method invocations") \ 1123 \ 1124 develop(bool, ICMissHistogram, false, \ 1125 "Produce histogram of IC misses") \ 1126 \ 1127 /* interpreter */ \ 1128 product_pd(bool, RewriteBytecodes, \ 1129 "Allow rewriting of bytecodes (bytecodes are not immutable)") \ 1130 \ 1131 product_pd(bool, RewriteFrequentPairs, \ 1132 "Rewrite frequently used bytecode pairs into a single bytecode") \ 1133 \ 1134 product(bool, PrintInterpreter, false, DIAGNOSTIC, \ 1135 "Print the generated interpreter code") \ 1136 \ 1137 product(bool, UseInterpreter, true, \ 1138 "Use interpreter for non-compiled methods") \ 1139 \ 1140 develop(bool, UseFastSignatureHandlers, true, \ 1141 "Use fast signature handlers for native calls") \ 1142 \ 1143 product(bool, UseLoopCounter, true, \ 1144 "Increment invocation counter on backward branch") \ 1145 \ 1146 product_pd(bool, UseOnStackReplacement, \ 1147 "Use on stack replacement, calls runtime if invoc. counter " \ 1148 "overflows in loop") \ 1149 \ 1150 develop(bool, TraceOnStackReplacement, false, \ 1151 "Trace on stack replacement") \ 1152 \ 1153 product_pd(bool, PreferInterpreterNativeStubs, \ 1154 "Use always interpreter stubs for native methods invoked via " \ 1155 "interpreter") \ 1156 \ 1157 product(bool, CountBytecodes, false, DIAGNOSTIC, \ 1158 "Count number of bytecodes executed") \ 1159 \ 1160 product(bool, CountBytecodesPerThread, false, DIAGNOSTIC, \ 1161 "Count number of bytecodes executed per thread") \ 1162 \ 1163 product(bool, PrintBytecodeHistogram, false, DIAGNOSTIC, \ 1164 "Print histogram of the executed bytecodes") \ 1165 \ 1166 product(double, PrintBytecodeHistogramCutoff, 0.01, \ 1167 "Print cutoff for histogram of the executed bytecodes") \ 1168 range(0.0, 100.0) \ 1169 \ 1170 develop(bool, PrintBytecodePairHistogram, false, \ 1171 "Print histogram of the executed bytecode pairs") \ 1172 \ 1173 product(bool, PrintSignatureHandlers, false, DIAGNOSTIC, \ 1174 "Print code generated for native method signature handlers") \ 1175 \ 1176 develop(bool, VerifyOops, false, \ 1177 "Do plausibility checks for oops") \ 1178 \ 1179 develop(bool, CheckUnhandledOops, false, \ 1180 "Check for unhandled oops in VM code") \ 1181 \ 1182 develop(bool, VerifyJNIFields, trueInDebug, \ 1183 "Verify jfieldIDs for instance fields") \ 1184 \ 1185 develop(bool, VerifyFPU, false, \ 1186 "Verify FPU state (check for NaN's, etc.)") \ 1187 \ 1188 develop(bool, VerifyActivationFrameSize, false, \ 1189 "Verify that activation frame didn't become smaller than its " \ 1190 "minimal size") \ 1191 \ 1192 develop(bool, TraceFrequencyInlining, false, \ 1193 "Trace frequency based inlining") \ 1194 \ 1195 develop_pd(bool, InlineIntrinsics, \ 1196 "Use intrinsics in Interpreter that can be statically resolved") \ 1197 \ 1198 product_pd(bool, ProfileInterpreter, \ 1199 "Profile at the bytecode level during interpretation") \ 1200 \ 1201 develop_pd(bool, ProfileTraps, \ 1202 "Profile deoptimization traps at the bytecode level") \ 1203 \ 1204 product(intx, ProfileMaturityPercentage, 20, \ 1205 "number of method invocations/branches (expressed as % of " \ 1206 "CompileThreshold) before using the method's profile") \ 1207 range(0, 100) \ 1208 \ 1209 product(bool, ForceProfiling, false, DIAGNOSTIC, \ 1210 "Eagerly allocate MDOs") \ 1211 \ 1212 product(bool, PrintMethodData, false, DIAGNOSTIC, \ 1213 "Print the results of +ProfileInterpreter at end of run") \ 1214 \ 1215 develop(bool, VerifyDataPointer, trueInDebug, \ 1216 "Verify the method data pointer during interpreter profiling") \ 1217 \ 1218 develop(bool, CrashGCForDumpingJavaThread, false, \ 1219 "Manually make GC thread crash then dump java stack trace; " \ 1220 "Test only") \ 1221 \ 1222 /* compilation */ \ 1223 product(bool, UseCompiler, true, \ 1224 "Use Just-In-Time compilation") \ 1225 \ 1226 develop(intx, CounterHalfLifeTime, 30, \ 1227 "Half-life time of invocation counters (in seconds)") \ 1228 \ 1229 product(bool, AlwaysCompileLoopMethods, false, \ 1230 "When using recompilation, never interpret methods " \ 1231 "containing loops") \ 1232 \ 1233 product(int, AllocatePrefetchStyle, 1, \ 1234 "0 = no prefetch, " \ 1235 "1 = generate prefetch instructions for each allocation, " \ 1236 "2 = use TLAB watermark to gate allocation prefetch, " \ 1237 "3 = generate one prefetch instruction per cache line") \ 1238 range(0, 3) \ 1239 \ 1240 product(int, AllocatePrefetchDistance, -1, \ 1241 "Distance to prefetch ahead of allocation pointer. " \ 1242 "-1: use system-specific value (automatically determined") \ 1243 range(-1, 512) \ 1244 \ 1245 product(int, AllocatePrefetchLines, 3, \ 1246 "Number of lines to prefetch ahead of array allocation pointer") \ 1247 range(1, 64) \ 1248 \ 1249 product(int, AllocateInstancePrefetchLines, 1, \ 1250 "Number of lines to prefetch ahead of instance allocation " \ 1251 "pointer") \ 1252 range(1, 64) \ 1253 \ 1254 product(int, AllocatePrefetchStepSize, 16, \ 1255 "Step size in bytes of sequential prefetch instructions") \ 1256 range(1, 512) \ 1257 constraint(AllocatePrefetchStepSizeConstraintFunc,AfterMemoryInit)\ 1258 \ 1259 product(intx, AllocatePrefetchInstr, 0, \ 1260 "Select instruction to prefetch ahead of allocation pointer") \ 1261 constraint(AllocatePrefetchInstrConstraintFunc, AfterMemoryInit) \ 1262 \ 1263 /* deoptimization */ \ 1264 product(bool, TraceDeoptimization, false, DIAGNOSTIC, \ 1265 "Trace deoptimization") \ 1266 \ 1267 develop(bool, PrintDeoptimizationDetails, false, \ 1268 "Print more information about deoptimization") \ 1269 \ 1270 develop(bool, DebugDeoptimization, false, \ 1271 "Tracing various information while debugging deoptimization") \ 1272 \ 1273 product(double, SelfDestructTimer, 0.0, \ 1274 "Will cause VM to terminate after a given time " \ 1275 "(in fractional minutes) " \ 1276 "(0.0 means off)") \ 1277 range(0.0, (double)max_intx) \ 1278 \ 1279 product(int, MaxJavaStackTraceDepth, 1024, \ 1280 "The maximum number of lines in the stack trace for Java " \ 1281 "exceptions (0 means all)") \ 1282 range(0, max_jint/2) \ 1283 \ 1284 /* notice: the max range value here is max_jint, not max_intx */ \ 1285 /* because of overflow issue */ \ 1286 product(intx, GuaranteedSafepointInterval, 0, DIAGNOSTIC, \ 1287 "Guarantee a safepoint (at least) every so many milliseconds " \ 1288 "(0 means none)") \ 1289 range(0, max_jint) \ 1290 \ 1291 product(intx, ServiceThreadCleanupInterval, 1000, DIAGNOSTIC, \ 1292 "Wake the ServiceThread to do periodic cleanup checks every so " \ 1293 "many milliseconds (0 means none)") \ 1294 range(0, max_jint) \ 1295 \ 1296 product(double, SafepointTimeoutDelay, 10000, \ 1297 "Delay in milliseconds for option SafepointTimeout; " \ 1298 "supports sub-millisecond resolution with fractional values.") \ 1299 range(0, max_jlongDouble LP64_ONLY(/MICROUNITS)) \ 1300 \ 1301 product(bool, UseSystemMemoryBarrier, false, \ 1302 "Try to enable system memory barrier if supported by OS") \ 1303 \ 1304 product(intx, NmethodSweepActivity, 4, \ 1305 "Removes cold nmethods from code cache if > 0. Higher values " \ 1306 "result in more aggressive sweeping") \ 1307 range(0, 2000) \ 1308 \ 1309 develop(intx, MallocCatchPtr, -1, \ 1310 "Hit breakpoint when mallocing/freeing this pointer") \ 1311 \ 1312 develop(int, StackPrintLimit, 100, \ 1313 "number of stack frames to print in VM-level stack dump") \ 1314 \ 1315 product(int, ErrorLogPrintCodeLimit, 3, DIAGNOSTIC, \ 1316 "max number of compiled code units to print in error log") \ 1317 range(0, VMError::max_error_log_print_code) \ 1318 \ 1319 develop(int, MaxElementPrintSize, 256, \ 1320 "maximum number of elements to print") \ 1321 \ 1322 develop(intx, MaxSubklassPrintSize, 4, \ 1323 "maximum number of subklasses to print when printing klass") \ 1324 \ 1325 develop(intx, MaxForceInlineLevel, 100, \ 1326 "maximum number of nested calls that are forced for inlining " \ 1327 "(using CompileCommand or marked w/ @ForceInline)") \ 1328 range(0, max_jint) \ 1329 \ 1330 develop(intx, MethodHistogramCutoff, 100, \ 1331 "The cutoff value for method invocation histogram (+CountCalls)") \ 1332 \ 1333 develop(intx, DeoptimizeALotInterval, 5, \ 1334 "Number of exits until DeoptimizeALot kicks in") \ 1335 \ 1336 develop(intx, ZombieALotInterval, 5, \ 1337 "Number of exits until ZombieALot kicks in") \ 1338 \ 1339 product(ccstr, MallocLimit, nullptr, DIAGNOSTIC, \ 1340 "Limit malloc allocation size from VM. Reaching a limit will " \ 1341 "trigger an action (see flag). This feature requires " \ 1342 "NativeMemoryTracking=summary or NativeMemoryTracking=detail." \ 1343 "Usage:" \ 1344 "\"-XX:MallocLimit=<size>[:<flag>]\" sets a total limit." \ 1345 "\"-XX:MallocLimit=<category>:<size>[:<flag>][,<category>:<size>[:<flag>] ...]\"" \ 1346 "sets one or more category-specific limits." \ 1347 "<flag> defines the action upon reaching the limit:" \ 1348 "\"fatal\": end VM with a fatal error at the allocation site" \ 1349 "\"oom\" : will mimic a native OOM" \ 1350 "If <flag> is omitted, \"fatal\" is the default." \ 1351 "Examples:\n" \ 1352 "-XX:MallocLimit=2g" \ 1353 "-XX:MallocLimit=2g:oom" \ 1354 "-XX:MallocLimit=compiler:200m:oom,code:100m") \ 1355 \ 1356 product(intx, TypeProfileWidth, 2, \ 1357 "Number of receiver types to record in call/cast profile") \ 1358 range(0, 8) \ 1359 \ 1360 develop(intx, BciProfileWidth, 2, \ 1361 "Number of return bci's to record in ret profile") \ 1362 \ 1363 product(intx, PerMethodRecompilationCutoff, 400, \ 1364 "After recompiling N times, stay in the interpreter (-1=>'Inf')") \ 1365 range(-1, max_intx) \ 1366 \ 1367 product(intx, PerBytecodeRecompilationCutoff, 200, \ 1368 "Per-BCI limit on repeated recompilation (-1=>'Inf')") \ 1369 range(-1, max_intx) \ 1370 \ 1371 product(intx, PerMethodTrapLimit, 100, \ 1372 "Limit on traps (of one kind) in a method (includes inlines)") \ 1373 range(0, max_jint) \ 1374 \ 1375 product(intx, PerMethodSpecTrapLimit, 5000, EXPERIMENTAL, \ 1376 "Limit on speculative traps (of one kind) in a method " \ 1377 "(includes inlines)") \ 1378 range(0, max_jint) \ 1379 \ 1380 product(intx, PerBytecodeTrapLimit, 4, \ 1381 "Limit on traps (of one kind) at a particular BCI") \ 1382 range(0, max_jint) \ 1383 \ 1384 product(int, SpecTrapLimitExtraEntries, 3, EXPERIMENTAL, \ 1385 "Extra method data trap entries for speculation") \ 1386 \ 1387 product(double, InlineFrequencyRatio, 0.25, DIAGNOSTIC, \ 1388 "Ratio of call site execution to caller method invocation") \ 1389 \ 1390 product(double, MinInlineFrequencyRatio, 0.0085, DIAGNOSTIC, \ 1391 "Minimum ratio of call site execution to caller method" \ 1392 "invocation to be considered for inlining") \ 1393 \ 1394 develop(intx, InlineThrowCount, 50, \ 1395 "Force inlining of interpreted methods that throw this often") \ 1396 range(0, max_jint) \ 1397 \ 1398 develop(intx, InlineThrowMaxSize, 200, \ 1399 "Force inlining of throwing methods smaller than this") \ 1400 range(0, max_jint) \ 1401 \ 1402 product(size_t, MetaspaceSize, NOT_LP64(16 * M) LP64_ONLY(21 * M), \ 1403 "Initial threshold (in bytes) at which a garbage collection " \ 1404 "is done to reduce Metaspace usage") \ 1405 constraint(MetaspaceSizeConstraintFunc,AfterErgo) \ 1406 \ 1407 product(size_t, MaxMetaspaceSize, max_uintx, \ 1408 "Maximum size of Metaspaces (in bytes)") \ 1409 constraint(MaxMetaspaceSizeConstraintFunc,AfterErgo) \ 1410 \ 1411 product(size_t, CompressedClassSpaceSize, 1*G, \ 1412 "Maximum size of class area in Metaspace when compressed " \ 1413 "class pointers are used") \ 1414 range(1*M, LP64_ONLY(4*G) NOT_LP64(max_uintx)) \ 1415 \ 1416 develop(size_t, CompressedClassSpaceBaseAddress, 0, \ 1417 "Force the class space to be allocated at this address or " \ 1418 "fails VM initialization (requires -Xshare=off.") \ 1419 \ 1420 develop(bool, RandomizeClassSpaceLocation, true, \ 1421 "Randomize location of class space.") \ 1422 \ 1423 product(bool, PrintMetaspaceStatisticsAtExit, false, DIAGNOSTIC, \ 1424 "Print metaspace statistics upon VM exit.") \ 1425 \ 1426 product(uintx, MinHeapFreeRatio, 40, MANAGEABLE, \ 1427 "The minimum percentage of heap free after GC to avoid expansion."\ 1428 " For most GCs this applies to the old generation. In G1 and" \ 1429 " ParallelGC it applies to the whole heap.") \ 1430 range(0, 100) \ 1431 constraint(MinHeapFreeRatioConstraintFunc,AfterErgo) \ 1432 \ 1433 product(uintx, MaxHeapFreeRatio, 70, MANAGEABLE, \ 1434 "The maximum percentage of heap free after GC to avoid shrinking."\ 1435 " For most GCs this applies to the old generation. In G1 and" \ 1436 " ParallelGC it applies to the whole heap.") \ 1437 range(0, 100) \ 1438 constraint(MaxHeapFreeRatioConstraintFunc,AfterErgo) \ 1439 \ 1440 product(intx, SoftRefLRUPolicyMSPerMB, 1000, \ 1441 "Number of milliseconds per MB of free space in the heap") \ 1442 range(0, max_intx) \ 1443 constraint(SoftRefLRUPolicyMSPerMBConstraintFunc,AfterMemoryInit) \ 1444 \ 1445 product(size_t, MinHeapDeltaBytes, ScaleForWordSize(128*K), \ 1446 "The minimum change in heap space due to GC (in bytes)") \ 1447 range(0, max_uintx) \ 1448 \ 1449 product(size_t, MinMetaspaceExpansion, ScaleForWordSize(256*K), \ 1450 "The minimum expansion of Metaspace (in bytes)") \ 1451 range(0, max_uintx) \ 1452 \ 1453 product(uint, MaxMetaspaceFreeRatio, 70, \ 1454 "The maximum percentage of Metaspace free after GC to avoid " \ 1455 "shrinking") \ 1456 range(0, 100) \ 1457 constraint(MaxMetaspaceFreeRatioConstraintFunc,AfterErgo) \ 1458 \ 1459 product(uint, MinMetaspaceFreeRatio, 40, \ 1460 "The minimum percentage of Metaspace free after GC to avoid " \ 1461 "expansion") \ 1462 range(0, 99) \ 1463 constraint(MinMetaspaceFreeRatioConstraintFunc,AfterErgo) \ 1464 \ 1465 product(size_t, MaxMetaspaceExpansion, ScaleForWordSize(4*M), \ 1466 "The maximum expansion of Metaspace without full GC (in bytes)") \ 1467 range(0, max_uintx) \ 1468 \ 1469 /* stack parameters */ \ 1470 product_pd(intx, StackYellowPages, \ 1471 "Number of yellow zone (recoverable overflows) pages of size " \ 1472 "4KB. If pages are bigger yellow zone is aligned up.") \ 1473 range(MIN_STACK_YELLOW_PAGES, (DEFAULT_STACK_YELLOW_PAGES+5)) \ 1474 \ 1475 product_pd(intx, StackRedPages, \ 1476 "Number of red zone (unrecoverable overflows) pages of size " \ 1477 "4KB. If pages are bigger red zone is aligned up.") \ 1478 range(MIN_STACK_RED_PAGES, (DEFAULT_STACK_RED_PAGES+2)) \ 1479 \ 1480 product_pd(intx, StackReservedPages, \ 1481 "Number of reserved zone (reserved to annotated methods) pages" \ 1482 " of size 4KB. If pages are bigger reserved zone is aligned up.") \ 1483 range(MIN_STACK_RESERVED_PAGES, (DEFAULT_STACK_RESERVED_PAGES+10))\ 1484 \ 1485 product(bool, RestrictReservedStack, true, \ 1486 "Restrict @ReservedStackAccess to trusted classes") \ 1487 \ 1488 /* greater stack shadow pages can't generate instruction to bang stack */ \ 1489 product_pd(intx, StackShadowPages, \ 1490 "Number of shadow zone (for overflow checking) pages of size " \ 1491 "4KB. If pages are bigger shadow zone is aligned up. " \ 1492 "This should exceed the depth of the VM and native call stack.") \ 1493 range(MIN_STACK_SHADOW_PAGES, (DEFAULT_STACK_SHADOW_PAGES+30)) \ 1494 \ 1495 product_pd(intx, ThreadStackSize, \ 1496 "Thread Stack Size (in Kbytes)") \ 1497 range(0, 1 * M) \ 1498 \ 1499 product_pd(intx, VMThreadStackSize, \ 1500 "Non-Java Thread Stack Size (in Kbytes)") \ 1501 range(0, max_intx/(1 * K)) \ 1502 \ 1503 product_pd(intx, CompilerThreadStackSize, \ 1504 "Compiler Thread Stack Size (in Kbytes)") \ 1505 range(0, max_intx/(1 * K)) \ 1506 \ 1507 develop_pd(size_t, JVMInvokeMethodSlack, \ 1508 "Stack space (bytes) required for JVM_InvokeMethod to complete") \ 1509 \ 1510 /* code cache parameters */ \ 1511 product_pd(uintx, CodeCacheSegmentSize, EXPERIMENTAL, \ 1512 "Code cache segment size (in bytes) - smallest unit of " \ 1513 "allocation") \ 1514 range(1, 1024) \ 1515 constraint(CodeCacheSegmentSizeConstraintFunc, AfterErgo) \ 1516 \ 1517 product_pd(intx, CodeEntryAlignment, EXPERIMENTAL, \ 1518 "Code entry alignment for generated code (in bytes)") \ 1519 constraint(CodeEntryAlignmentConstraintFunc, AfterErgo) \ 1520 \ 1521 product_pd(intx, OptoLoopAlignment, \ 1522 "Align inner loops to zero relative to this modulus") \ 1523 range(1, 128) \ 1524 constraint(OptoLoopAlignmentConstraintFunc, AfterErgo) \ 1525 \ 1526 product_pd(uintx, InitialCodeCacheSize, \ 1527 "Initial code cache size (in bytes)") \ 1528 constraint(VMPageSizeConstraintFunc, AtParse) \ 1529 \ 1530 develop_pd(uintx, CodeCacheMinimumUseSpace, \ 1531 "Minimum code cache size (in bytes) required to start VM.") \ 1532 range(0, max_uintx) \ 1533 \ 1534 product(bool, SegmentedCodeCache, false, \ 1535 "Use a segmented code cache") \ 1536 \ 1537 product_pd(uintx, ReservedCodeCacheSize, \ 1538 "Reserved code cache size (in bytes) - maximum code cache size") \ 1539 constraint(VMPageSizeConstraintFunc, AtParse) \ 1540 \ 1541 product_pd(uintx, NonProfiledCodeHeapSize, \ 1542 "Size of code heap with non-profiled methods (in bytes)") \ 1543 range(0, max_uintx) \ 1544 \ 1545 product_pd(uintx, ProfiledCodeHeapSize, \ 1546 "Size of code heap with profiled methods (in bytes)") \ 1547 range(0, max_uintx) \ 1548 \ 1549 product_pd(uintx, NonNMethodCodeHeapSize, \ 1550 "Size of code heap with non-nmethods (in bytes)") \ 1551 constraint(VMPageSizeConstraintFunc, AtParse) \ 1552 \ 1553 product_pd(uintx, CodeCacheExpansionSize, \ 1554 "Code cache expansion size (in bytes)") \ 1555 range(32*K, max_uintx) \ 1556 \ 1557 product_pd(uintx, CodeCacheMinBlockLength, DIAGNOSTIC, \ 1558 "Minimum number of segments in a code cache block") \ 1559 range(1, 100) \ 1560 \ 1561 develop(bool, ExitOnFullCodeCache, false, \ 1562 "Exit the VM if we fill the code cache") \ 1563 \ 1564 product(bool, UseCodeCacheFlushing, true, \ 1565 "Remove cold/old nmethods from the code cache") \ 1566 \ 1567 product(double, SweeperThreshold, 15.0, \ 1568 "Threshold when a code cache unloading GC is invoked." \ 1569 "Value is percentage of ReservedCodeCacheSize.") \ 1570 range(0.0, 100.0) \ 1571 \ 1572 product(uintx, StartAggressiveSweepingAt, 10, \ 1573 "Start aggressive sweeping if X[%] of the code cache is free." \ 1574 "Segmented code cache: X[%] of the non-profiled heap." \ 1575 "Non-segmented code cache: X[%] of the total code cache") \ 1576 range(0, 100) \ 1577 \ 1578 /* interpreter debugging */ \ 1579 develop(intx, BinarySwitchThreshold, 5, \ 1580 "Minimal number of lookupswitch entries for rewriting to binary " \ 1581 "switch") \ 1582 \ 1583 develop(intx, StopInterpreterAt, 0, \ 1584 "Stop interpreter execution at specified bytecode number") \ 1585 \ 1586 develop(intx, TraceBytecodesAt, 0, \ 1587 "Trace bytecodes starting with specified bytecode number") \ 1588 \ 1589 develop(intx, TraceBytecodesStopAt, 0, \ 1590 "Stop bytecode tracing at the specified bytecode number") \ 1591 \ 1592 /* Priorities */ \ 1593 product_pd(bool, UseThreadPriorities, "Use native thread priorities") \ 1594 \ 1595 product(int, ThreadPriorityPolicy, 0, \ 1596 "0 : Normal. "\ 1597 " VM chooses priorities that are appropriate for normal "\ 1598 " applications. "\ 1599 " On Windows applications are allowed to use higher native "\ 1600 " priorities. However, with ThreadPriorityPolicy=0, VM will "\ 1601 " not use the highest possible native priority, "\ 1602 " THREAD_PRIORITY_TIME_CRITICAL, as it may interfere with "\ 1603 " system threads. On Linux thread priorities are ignored "\ 1604 " because the OS does not support static priority in "\ 1605 " SCHED_OTHER scheduling class which is the only choice for "\ 1606 " non-root, non-realtime applications. "\ 1607 "1 : Aggressive. "\ 1608 " Java thread priorities map over to the entire range of "\ 1609 " native thread priorities. Higher Java thread priorities map "\ 1610 " to higher native thread priorities. This policy should be "\ 1611 " used with care, as sometimes it can cause performance "\ 1612 " degradation in the application and/or the entire system. On "\ 1613 " Linux/BSD/macOS this policy requires root privilege or an "\ 1614 " extended capability.") \ 1615 range(0, 1) \ 1616 \ 1617 product(bool, ThreadPriorityVerbose, false, \ 1618 "Print priority changes") \ 1619 \ 1620 product(int, CompilerThreadPriority, -1, \ 1621 "The native priority at which compiler threads should run " \ 1622 "(-1 means no change)") \ 1623 range(min_jint, max_jint) \ 1624 \ 1625 product(int, VMThreadPriority, -1, \ 1626 "The native priority at which the VM thread should run " \ 1627 "(-1 means no change)") \ 1628 range(-1, 127) \ 1629 \ 1630 product(int, JavaPriority1_To_OSPriority, -1, \ 1631 "Map Java priorities to OS priorities") \ 1632 range(-1, 127) \ 1633 \ 1634 product(int, JavaPriority2_To_OSPriority, -1, \ 1635 "Map Java priorities to OS priorities") \ 1636 range(-1, 127) \ 1637 \ 1638 product(int, JavaPriority3_To_OSPriority, -1, \ 1639 "Map Java priorities to OS priorities") \ 1640 range(-1, 127) \ 1641 \ 1642 product(int, JavaPriority4_To_OSPriority, -1, \ 1643 "Map Java priorities to OS priorities") \ 1644 range(-1, 127) \ 1645 \ 1646 product(int, JavaPriority5_To_OSPriority, -1, \ 1647 "Map Java priorities to OS priorities") \ 1648 range(-1, 127) \ 1649 \ 1650 product(int, JavaPriority6_To_OSPriority, -1, \ 1651 "Map Java priorities to OS priorities") \ 1652 range(-1, 127) \ 1653 \ 1654 product(int, JavaPriority7_To_OSPriority, -1, \ 1655 "Map Java priorities to OS priorities") \ 1656 range(-1, 127) \ 1657 \ 1658 product(int, JavaPriority8_To_OSPriority, -1, \ 1659 "Map Java priorities to OS priorities") \ 1660 range(-1, 127) \ 1661 \ 1662 product(int, JavaPriority9_To_OSPriority, -1, \ 1663 "Map Java priorities to OS priorities") \ 1664 range(-1, 127) \ 1665 \ 1666 product(int, JavaPriority10_To_OSPriority,-1, \ 1667 "Map Java priorities to OS priorities") \ 1668 range(-1, 127) \ 1669 \ 1670 product(bool, UseCriticalJavaThreadPriority, false, EXPERIMENTAL, \ 1671 "Java thread priority 10 maps to critical scheduling priority") \ 1672 \ 1673 product(bool, UseCriticalCompilerThreadPriority, false, EXPERIMENTAL, \ 1674 "Compiler thread(s) run at critical scheduling priority") \ 1675 \ 1676 develop(intx, NewCodeParameter, 0, \ 1677 "Testing Only: Create a dedicated integer parameter before " \ 1678 "putback") \ 1679 \ 1680 /* new oopmap storage allocation */ \ 1681 develop(intx, MinOopMapAllocation, 8, \ 1682 "Minimum number of OopMap entries in an OopMapSet") \ 1683 \ 1684 /* recompilation */ \ 1685 product_pd(intx, CompileThreshold, \ 1686 "number of interpreted method invocations before (re-)compiling") \ 1687 constraint(CompileThresholdConstraintFunc, AfterErgo) \ 1688 \ 1689 product_pd(bool, TieredCompilation, \ 1690 "Enable tiered compilation") \ 1691 \ 1692 /* Properties for Java libraries */ \ 1693 \ 1694 product(uint64_t, MaxDirectMemorySize, 0, \ 1695 "Maximum total size of NIO direct-buffer allocations. " \ 1696 "Ignored if not explicitly set.") \ 1697 range(0, max_jlong) \ 1698 \ 1699 /* Flags used for temporary code during development */ \ 1700 \ 1701 product(bool, UseNewCode, false, DIAGNOSTIC, \ 1702 "Testing Only: Use the new version while testing") \ 1703 \ 1704 product(bool, UseNewCode2, false, DIAGNOSTIC, \ 1705 "Testing Only: Use the new version while testing") \ 1706 \ 1707 product(bool, UseNewCode3, false, DIAGNOSTIC, \ 1708 "Testing Only: Use the new version while testing") \ 1709 \ 1710 develop(bool, UseDebuggerErgo, false, \ 1711 "Debugging Only: Adjust the VM to be more debugger-friendly. " \ 1712 "Turns on the other UseDebuggerErgo* flags") \ 1713 \ 1714 develop(bool, UseDebuggerErgo1, false, \ 1715 "Debugging Only: Enable workarounds for debugger induced " \ 1716 "os::processor_id() >= os::processor_count() problems") \ 1717 \ 1718 develop(bool, UseDebuggerErgo2, false, \ 1719 "Debugging Only: Limit the number of spawned JVM threads") \ 1720 \ 1721 develop(bool, EnableJVMTIStackDepthAsserts, true, \ 1722 "Enable JVMTI asserts related to stack depth checks") \ 1723 \ 1724 /* flags for performance data collection */ \ 1725 \ 1726 product(bool, UsePerfData, true, \ 1727 "Flag to disable jvmstat instrumentation for performance testing "\ 1728 "and problem isolation purposes") \ 1729 \ 1730 product(bool, PerfDataSaveToFile, false, \ 1731 "Save PerfData memory to hsperfdata_<pid> file on exit") \ 1732 \ 1733 product(ccstr, PerfDataSaveFile, nullptr, \ 1734 "Save PerfData memory to the specified absolute pathname. " \ 1735 "The string %p in the file name (if present) " \ 1736 "will be replaced by pid") \ 1737 \ 1738 product(int, PerfDataSamplingInterval, 50, \ 1739 "Data sampling interval (in milliseconds)") \ 1740 range(PeriodicTask::min_interval, max_jint) \ 1741 constraint(PerfDataSamplingIntervalFunc, AfterErgo) \ 1742 \ 1743 product(bool, PerfDisableSharedMem, false, \ 1744 "Store performance data in standard memory") \ 1745 \ 1746 product(int, PerfDataMemorySize, 64*K, \ 1747 "Size of performance data memory region. Will be rounded " \ 1748 "up to a multiple of the native os page size.") \ 1749 range(128, 32*64*K) \ 1750 \ 1751 product(int, PerfMaxStringConstLength, 1024, \ 1752 "Maximum PerfStringConstant string length before truncation") \ 1753 range(32, 32*K) \ 1754 \ 1755 product(bool, PerfAllowAtExitRegistration, false, \ 1756 "Allow registration of atexit() methods") \ 1757 \ 1758 product(bool, PerfBypassFileSystemCheck, false, \ 1759 "Bypass Win32 file system criteria checks (Windows Only)") \ 1760 \ 1761 product(int, UnguardOnExecutionViolation, 0, \ 1762 "Unguard page and retry on no-execute fault (Win32 only) " \ 1763 "0=off, 1=conservative, 2=aggressive") \ 1764 range(0, 2) \ 1765 \ 1766 /* Serviceability Support */ \ 1767 \ 1768 product(bool, ManagementServer, false, \ 1769 "Create JMX Management Server") \ 1770 \ 1771 product(bool, DisableAttachMechanism, false, \ 1772 "Disable mechanism that allows tools to attach to this VM") \ 1773 \ 1774 product(bool, StartAttachListener, false, \ 1775 "Always start Attach Listener at VM startup") \ 1776 \ 1777 product(bool, EnableDynamicAgentLoading, true, \ 1778 "Allow tools to load agents with the attach mechanism") \ 1779 \ 1780 product(bool, PrintConcurrentLocks, false, MANAGEABLE, \ 1781 "Print java.util.concurrent locks in thread dump") \ 1782 \ 1783 product(bool, PrintMethodHandleStubs, false, DIAGNOSTIC, \ 1784 "Print generated stub code for method handles") \ 1785 \ 1786 product(bool, VerifyMethodHandles, trueInDebug, DIAGNOSTIC, \ 1787 "perform extra checks when constructing method handles") \ 1788 \ 1789 product(bool, ShowHiddenFrames, false, DIAGNOSTIC, \ 1790 "show method handle implementation frames (usually hidden)") \ 1791 \ 1792 product(bool, ShowCarrierFrames, false, DIAGNOSTIC, \ 1793 "show virtual threads' carrier frames in exceptions") \ 1794 \ 1795 product(bool, TrustFinalNonStaticFields, false, EXPERIMENTAL, \ 1796 "trust final non-static declarations for constant folding") \ 1797 \ 1798 product(bool, FoldStableValues, true, DIAGNOSTIC, \ 1799 "Optimize loads from stable fields (marked w/ @Stable)") \ 1800 \ 1801 product(int, UseBootstrapCallInfo, 1, DIAGNOSTIC, \ 1802 "0: when resolving InDy or ConDy, force all BSM arguments to be " \ 1803 "resolved before the bootstrap method is called; 1: when a BSM " \ 1804 "that may accept a BootstrapCallInfo is detected, use that API " \ 1805 "to pass BSM arguments, which allows the BSM to delay their " \ 1806 "resolution; 2+: stress test the BCI API by calling more BSMs " \ 1807 "via that API, instead of with the eagerly-resolved array.") \ 1808 \ 1809 product(bool, PauseAtStartup, false, DIAGNOSTIC, \ 1810 "Causes the VM to pause at startup time and wait for the pause " \ 1811 "file to be removed (default: ./vm.paused.<pid>)") \ 1812 \ 1813 product(ccstr, PauseAtStartupFile, nullptr, DIAGNOSTIC, \ 1814 "The file to create and for whose removal to await when pausing " \ 1815 "at startup. (default: ./vm.paused.<pid>)") \ 1816 \ 1817 product(bool, PauseAtExit, false, DIAGNOSTIC, \ 1818 "Pause and wait for keypress on exit if a debugger is attached") \ 1819 \ 1820 product(bool, DTraceMethodProbes, false, \ 1821 "Enable dtrace tool probes for method-entry and method-exit") \ 1822 \ 1823 product(bool, DTraceAllocProbes, false, \ 1824 "Enable dtrace tool probes for object allocation") \ 1825 \ 1826 product(bool, DTraceMonitorProbes, false, \ 1827 "Enable dtrace tool probes for monitor events") \ 1828 \ 1829 product(bool, RelaxAccessControlCheck, false, \ 1830 "Relax the access control checks in the verifier") \ 1831 \ 1832 product(uintx, StringTableSize, defaultStringTableSize, \ 1833 "Number of buckets in the interned String table " \ 1834 "(will be rounded to nearest higher power of 2)") \ 1835 range(minimumStringTableSize, 16777216ul /* 2^24 */) \ 1836 \ 1837 product(uintx, SymbolTableSize, defaultSymbolTableSize, EXPERIMENTAL, \ 1838 "Number of buckets in the JVM internal Symbol table") \ 1839 range(minimumSymbolTableSize, 16777216ul /* 2^24 */) \ 1840 \ 1841 product(bool, UseStringDeduplication, false, \ 1842 "Use string deduplication") \ 1843 \ 1844 product(uint, StringDeduplicationAgeThreshold, 3, \ 1845 "A string must reach this age (or be promoted to an old region) " \ 1846 "to be considered for deduplication") \ 1847 range(1, markWord::max_age) \ 1848 \ 1849 product(size_t, StringDeduplicationInitialTableSize, 500, EXPERIMENTAL, \ 1850 "Approximate initial number of buckets in the table") \ 1851 range(1, 1 * G) \ 1852 \ 1853 product(double, StringDeduplicationGrowTableLoad, 14.0, EXPERIMENTAL, \ 1854 "Entries per bucket above which the table should be expanded") \ 1855 range(0.1, 1000.0) \ 1856 \ 1857 product(double, StringDeduplicationShrinkTableLoad, 1.0, EXPERIMENTAL, \ 1858 "Entries per bucket below which the table should be shrunk") \ 1859 range(0.01, 100.0) \ 1860 \ 1861 product(double, StringDeduplicationTargetTableLoad, 7.0, EXPERIMENTAL, \ 1862 "Desired entries per bucket when resizing the table") \ 1863 range(0.01, 1000.0) \ 1864 \ 1865 product(size_t, StringDeduplicationCleanupDeadMinimum, 100, EXPERIMENTAL, \ 1866 "Minimum number of dead table entries for cleaning the table") \ 1867 \ 1868 product(int, StringDeduplicationCleanupDeadPercent, 5, EXPERIMENTAL, \ 1869 "Minimum percentage of dead table entries for cleaning the table") \ 1870 range(1, 100) \ 1871 \ 1872 product(bool, StringDeduplicationResizeALot, false, DIAGNOSTIC, \ 1873 "Force more frequent table resizing") \ 1874 \ 1875 product(uint64_t, StringDeduplicationHashSeed, 0, DIAGNOSTIC, \ 1876 "Seed for the table hashing function; 0 requests computed seed") \ 1877 \ 1878 product(bool, WhiteBoxAPI, false, DIAGNOSTIC, \ 1879 "Enable internal testing APIs") \ 1880 \ 1881 product(bool, AlwaysAtomicAccesses, false, EXPERIMENTAL, \ 1882 "Accesses to all variables should always be atomic") \ 1883 \ 1884 product(bool, UseUnalignedAccesses, false, DIAGNOSTIC, \ 1885 "Use unaligned memory accesses in Unsafe") \ 1886 \ 1887 product_pd(bool, PreserveFramePointer, \ 1888 "Use the FP register for holding the frame pointer " \ 1889 "and not as a general purpose register.") \ 1890 \ 1891 product(size_t, AsyncLogBufferSize, 2*M, \ 1892 "Memory budget (in bytes) for the buffer of Asynchronous " \ 1893 "Logging (-Xlog:async).") \ 1894 range(100*K, 50*M) \ 1895 \ 1896 product(bool, CheckIntrinsics, true, DIAGNOSTIC, \ 1897 "When a class C is loaded, check that " \ 1898 "(1) all intrinsics defined by the VM for class C are present "\ 1899 "in the loaded class file and are marked with the " \ 1900 "@IntrinsicCandidate annotation, that " \ 1901 "(2) there is an intrinsic registered for all loaded methods " \ 1902 "that are annotated with the @IntrinsicCandidate annotation, " \ 1903 "and that " \ 1904 "(3) no orphan methods exist for class C (i.e., methods for " \ 1905 "which the VM declares an intrinsic but that are not declared "\ 1906 "in the loaded class C. " \ 1907 "Check (3) is available only in debug builds.") \ 1908 \ 1909 product_pd(intx, InitArrayShortSize, DIAGNOSTIC, \ 1910 "Threshold small size (in bytes) for clearing arrays. " \ 1911 "Anything this size or smaller may get converted to discrete " \ 1912 "scalar stores.") \ 1913 range(0, max_intx) \ 1914 constraint(InitArrayShortSizeConstraintFunc, AfterErgo) \ 1915 \ 1916 product(ccstr, AllocateHeapAt, nullptr, \ 1917 "Path to the directory where a temporary file will be created " \ 1918 "to use as the backing store for Java Heap.") \ 1919 \ 1920 product_pd(bool, VMContinuations, EXPERIMENTAL, \ 1921 "Enable VM continuations support") \ 1922 \ 1923 develop(bool, LoomDeoptAfterThaw, false, \ 1924 "Deopt stack after thaw") \ 1925 \ 1926 develop(bool, LoomVerifyAfterThaw, false, \ 1927 "Verify stack after thaw") \ 1928 \ 1929 develop(bool, VerifyContinuations, false, \ 1930 "Verify continuation consistency") \ 1931 \ 1932 develop(bool, UseContinuationFastPath, true, \ 1933 "Use fast-path frame walking in continuations") \ 1934 \ 1935 develop(int, VerifyMetaspaceInterval, DEBUG_ONLY(500) NOT_DEBUG(0), \ 1936 "Run periodic metaspace verifications (0 - none, " \ 1937 "1 - always, >1 every nth interval)") \ 1938 \ 1939 product(bool, ShowRegistersOnAssert, true, DIAGNOSTIC, \ 1940 "On internal errors, include registers in error report.") \ 1941 \ 1942 product(bool, UseSwitchProfiling, true, DIAGNOSTIC, \ 1943 "leverage profiling for table/lookup switch") \ 1944 \ 1945 develop(bool, TraceMemoryWriteback, false, \ 1946 "Trace memory writeback operations") \ 1947 \ 1948 JFR_ONLY(product(bool, FlightRecorder, false, \ 1949 "(Deprecated) Enable Flight Recorder")) \ 1950 \ 1951 JFR_ONLY(product(ccstr, FlightRecorderOptions, nullptr, \ 1952 "Flight Recorder options")) \ 1953 \ 1954 JFR_ONLY(product(ccstr, StartFlightRecording, nullptr, \ 1955 "Start flight recording with options")) \ 1956 \ 1957 product(bool, UseFastUnorderedTimeStamps, false, EXPERIMENTAL, \ 1958 "Use platform unstable time where supported for timestamps only") \ 1959 \ 1960 product(bool, DeoptimizeNMethodBarriersALot, false, DIAGNOSTIC, \ 1961 "Make nmethod barriers deoptimise a lot.") \ 1962 \ 1963 develop(bool, VerifyCrossModifyFence, \ 1964 false AARCH64_ONLY(DEBUG_ONLY(||true)), \ 1965 "Mark all threads after a safepoint, and clear on a modify " \ 1966 "fence. Add cleanliness checks.") \ 1967 \ 1968 product(int, LockingMode, LM_LIGHTWEIGHT, \ 1969 "(Deprecated) Select locking mode: " \ 1970 "0: (Deprecated) monitors only (LM_MONITOR), " \ 1971 "1: (Deprecated) monitors & legacy stack-locking (LM_LEGACY), " \ 1972 "2: monitors & new lightweight locking (LM_LIGHTWEIGHT, default)") \ 1973 range(0, 2) \ 1974 \ 1975 product(uint, TrimNativeHeapInterval, 0, \ 1976 "Interval, in ms, at which the JVM will trim the native heap if " \ 1977 "the platform supports that. Lower values will reclaim memory " \ 1978 "more eagerly at the cost of higher overhead. A value of 0 " \ 1979 "(default) disables native heap trimming.") \ 1980 range(0, UINT_MAX) \ 1981 \ 1982 product(bool, ProfileVMLocks, false, DIAGNOSTIC, \ 1983 "Profile VM locks usage on main thread") \ 1984 \ 1985 product(bool, ProfileVMCalls, false, DIAGNOSTIC, \ 1986 "Profile VM calls on main thread") \ 1987 \ 1988 product(bool, ProfileVMOps, true, DIAGNOSTIC, \ 1989 "Profile VM operations on main thread") \ 1990 \ 1991 product(bool, ProfileRuntimeCalls, false, DIAGNOSTIC, \ 1992 "Profile calls into VM runtime on main thread") \ 1993 \ 1994 develop(bool, SimulateFullAddressSpace, false, \ 1995 "Simulates a very populated, fragmented address space; no " \ 1996 "targeted reservations will succeed.") \ 1997 \ 1998 product(bool, ProfileExceptionHandlers, true, \ 1999 "Profile exception handlers") \ 2000 \ 2001 product(bool, AlwaysRecordEvolDependencies, true, EXPERIMENTAL, \ 2002 "Unconditionally record nmethod dependencies on class " \ 2003 "rewriting/transformation independently of the JVMTI " \ 2004 "can_{retransform/redefine}_classes capabilities.") \ 2005 \ 2006 product(bool, TraceThreadTime, false, \ 2007 "Enable tracing of thread time in Perf counters") \ 2008 \ 2009 product(bool, UseSecondarySupersCache, true, DIAGNOSTIC, \ 2010 "Use secondary supers cache during subtype checks.") \ 2011 \ 2012 product(bool, UseSecondarySupersTable, false, DIAGNOSTIC, \ 2013 "Use hash table to lookup secondary supers.") \ 2014 \ 2015 product(bool, VerifySecondarySupers, false, DIAGNOSTIC, \ 2016 "Check that linear and hashed secondary lookups return the same result.") \ 2017 \ 2018 product(bool, StressSecondarySupers, false, DIAGNOSTIC, \ 2019 "Use a terrible hash function in order to generate many collisions.") \ 2020 2021 2022 // end of RUNTIME_FLAGS 2023 2024 DECLARE_FLAGS(LP64_RUNTIME_FLAGS) 2025 DECLARE_ARCH_FLAGS(ARCH_FLAGS) 2026 DECLARE_FLAGS(RUNTIME_FLAGS) 2027 DECLARE_FLAGS(RUNTIME_OS_FLAGS) 2028 2029 #endif // SHARE_RUNTIME_GLOBALS_HPP