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