270 // be able to build a fully supported product that nonetheless also |
270 // be able to build a fully supported product that nonetheless also |
271 // ships with some unsupported, lightly tested, experimental features. |
271 // ships with some unsupported, lightly tested, experimental features. |
272 // Like the UnlockDiagnosticVMOptions flag above, there is a corresponding |
272 // Like the UnlockDiagnosticVMOptions flag above, there is a corresponding |
273 // UnlockExperimentalVMOptions flag, which allows the control and |
273 // UnlockExperimentalVMOptions flag, which allows the control and |
274 // modification of the experimental flags. |
274 // modification of the experimental flags. |
|
275 // |
|
276 // Nota bene: neither diagnostic nor experimental options should be used casually, |
|
277 // and they are not supported on production loads, except under explicit |
|
278 // direction from support engineers. |
275 // |
279 // |
276 // manageable flags are writeable external product flags. |
280 // manageable flags are writeable external product flags. |
277 // They are dynamically writeable through the JDK management interface |
281 // They are dynamically writeable through the JDK management interface |
278 // (com.sun.management.HotSpotDiagnosticMXBean API) and also through JConsole. |
282 // (com.sun.management.HotSpotDiagnosticMXBean API) and also through JConsole. |
279 // These flags are external exported interface (see CCC). The list of |
283 // These flags are external exported interface (see CCC). The list of |
632 "Zap freed VM handle space with 0xBCBCBCBC") \ |
636 "Zap freed VM handle space with 0xBCBCBCBC") \ |
633 \ |
637 \ |
634 develop(bool, ZapJNIHandleArea, trueInDebug, \ |
638 develop(bool, ZapJNIHandleArea, trueInDebug, \ |
635 "Zap freed JNI handle space with 0xFEFEFEFE") \ |
639 "Zap freed JNI handle space with 0xFEFEFEFE") \ |
636 \ |
640 \ |
|
641 notproduct(bool, ZapStackSegments, trueInDebug, \ |
|
642 "Zap allocated/freed Stack segments with 0xFADFADED") \ |
|
643 \ |
637 develop(bool, ZapUnusedHeapArea, trueInDebug, \ |
644 develop(bool, ZapUnusedHeapArea, trueInDebug, \ |
638 "Zap unused heap space with 0xBAADBABE") \ |
645 "Zap unused heap space with 0xBAADBABE") \ |
639 \ |
646 \ |
640 develop(bool, TraceZapUnusedHeapArea, false, \ |
647 develop(bool, TraceZapUnusedHeapArea, false, \ |
641 "Trace zapping of unused heap space") \ |
648 "Trace zapping of unused heap space") \ |
1797 "(other young collectors) ") \ |
1804 "(other young collectors) ") \ |
1798 \ |
1805 \ |
1799 develop(uintx, PromotionFailureALotInterval, 5, \ |
1806 develop(uintx, PromotionFailureALotInterval, 5, \ |
1800 "Total collections between promotion failures alot") \ |
1807 "Total collections between promotion failures alot") \ |
1801 \ |
1808 \ |
1802 develop(intx, WorkStealingSleepMillis, 1, \ |
1809 experimental(intx, WorkStealingSleepMillis, 1, \ |
1803 "Sleep time when sleep is used for yields") \ |
1810 "Sleep time when sleep is used for yields") \ |
1804 \ |
1811 \ |
1805 develop(uintx, WorkStealingYieldsBeforeSleep, 1000, \ |
1812 experimental(uintx, WorkStealingYieldsBeforeSleep, 1000, \ |
1806 "Number of yields before a sleep is done during workstealing") \ |
1813 "Number of yields before a sleep is done during workstealing") \ |
1807 \ |
1814 \ |
1808 develop(uintx, WorkStealingHardSpins, 4096, \ |
1815 experimental(uintx, WorkStealingHardSpins, 4096, \ |
1809 "Number of iterations in a spin loop between checks on " \ |
1816 "Number of iterations in a spin loop between checks on " \ |
1810 "time out of hard spin") \ |
1817 "time out of hard spin") \ |
1811 \ |
1818 \ |
1812 develop(uintx, WorkStealingSpinToYieldRatio, 10, \ |
1819 experimental(uintx, WorkStealingSpinToYieldRatio, 10, \ |
1813 "Ratio of hard spins to calls to yield") \ |
1820 "Ratio of hard spins to calls to yield") \ |
1814 \ |
1821 \ |
1815 product(uintx, PreserveMarkStackSize, 1024, \ |
1822 product(uintx, PreserveMarkStackSize, 1024, \ |
1816 "Size for stack used in promotion failure handling") \ |
1823 "Size for stack used in promotion failure handling") \ |
1817 \ |
1824 \ |