Java CMSinitiatingOccinecyFraction=N是否可以在增量模式下与CMS一起使用？

我们在JDK1.5Update 11上运行CMS收集器时遇到了一些并发模式故障。我试着从这里和其他博客上学习《太阳报》和其他技巧。我们目前正在运行以下程序：

-Xms1792m -Xmx1792m -XX:NewSize=512m -XX:MaxNewSize=512m -XX:PermSize=384m -XX:MaxPermSize=384m -Xss128k -XX:+DisableExplicitGC -XX:+UseConcMarkSweepGC -XX:+UseParNewGC -XX:+CMSParallelRemarkEnabled -XX:+CMSIncrementalMode -XX:-CMSIncrementalPacing -XX:CMSIncrementalDutyCycle=30 -XX:CMSIncrementalSafetyFactor=30 -XX:+CMSPermGenSweepingEnabled -XX:+CMSClassUnloadingEnabled -verbosegc -XX:+PrintGCDetails -XX:+PrintGCTimeStamps -XX:-TraceClassUnloading -server 

服务器通常可以正常运行2-3天，在这一天中，我只会看到1到2个并发模式故障，但在这之后，我开始看到故障显著增加。我们正在调查内存缓慢泄漏的可能性，但与此同时，暂停变得越来越糟糕，有时每20分钟多达20秒，需要我们重新启动（然后再持续2-3天）

我们在一台2核4 GB的机器上运行，因此启用了增量模式，因为没有cpu峰值导致性能问题

所以，我的问题是，为了让CMS尽早启动，以避免失败，我想指定CMSinitiatingOccupencyFraction=50（首先）。但是，对于当CMS收集器处于增量模式时是否可以使用-XX:cmSinitiatingOccinecyFraction=N标志，我找不到明确的答案

如果无法同时使用这两种模式，我可以采取哪些其他措施来减少并发模式故障的数量？我们不能将堆大小增加到现在的水平，我已经尝试将安全系数增加到30，将占空比增加到30-我是否应该尝试将这些增加更多

e、 g.日志：

363419.049: [CMS-concurrent-sweep-start]
363420.908: [GC 363420.909: [ParNew: 523392K->0K(523840K), 0.0795650 secs] 1652124K->1136058K(1834560K), 0.0803380 secs]
363429.886: [GC 363429.887: [ParNew: 523392K->0K(523840K), 0.0706960 secs] 1659196K->1144335K(1834560K), 0.0714890 secs]
363432.566: [Full GC 363432.566: [ParNew: 520584K->0K(523840K), 0.0769280 secs] 1672290K->1169919K(1834560K), 0.0775740 secs]
363439.937: [Full GC 363439.938: [ParNew (promotion failed): 523840K->523840K(523840K), 0.3404490 secs] 1690606K->1712399K(1834560K), 0.3412880 secs]
363440.280: [GC 363440.280: [ParNew (promotion failed): 523840K->523840K(523840K), 0.2211610 secs]363440.502: [CMS363440.935: [CMS-concurrent-sweep: 4.549/21.886 secs]
 (concurrent mode failure): 1188559K->1047404K(1310720K), 9.2920010 secs] 1712399K->1047404K(1834560K), 9.5137760 secs]
363451.421: [GC [1 CMS-initial-mark: 1047404K(1310720K)] 1245963K(1834560K), 0.1440540 secs]
363453.521: [CMS-concurrent-mark-start]
363453.523: [GC 363453.523: [ParNew: 523840K->0K(523840K), 0.1876280 secs] 1576618K->1175643K(1834560K), 0.1879520 secs]
363458.913: [GC 363458.913: [ParNew: 523097K->0K(523840K), 0.0639300 secs] 1698741K->1181843K(1834560K), 0.0644500 secs]
363468.068: [GC 363468.068: [ParNew: 523392K->0K(523840K), 0.0758130 secs] 1705235K->1187900K(1834560K), 0.0763340 secs]
363472.286: [CMS-concurrent-mark: 6.721/18.765 secs]
363472.286: [CMS-concurrent-preclean-start]
363472.493: [CMS-concurrent-preclean: 0.182/0.207 secs]
363472.493: [CMS-concurrent-abortable-preclean-start]
363476.433: [GC 363476.433: [ParNew: 523392K->0K(523840K), 0.0798890 secs] 1711292K->1193725K(1834560K), 0.0804050 secs]
363485.438: [CMS-concurrent-abortable-preclean: 0.598/12.945 secs]
363485.440: [GC[YG occupancy: 268431 K (523840 K)]363485.441: [Rescan (parallel) , 0.3050930 secs]363485.746: [weak refs processing, 0.0183180 secs] [1 CMS-remark: 1193725K(1310720K)] 1462157K(1834560K), 0.3241100 secs]
363485.772: [CMS-concurrent-sweep-start]
363486.619: [CMS-concurrent-sweep: 0.847/0.847 secs]
363486.620: [CMS-concurrent-reset-start]
363486.665: [CMS-concurrent-reset: 0.046/0.046 secs]
363487.664: [GC 363487.664: [ParNew: 523392K->0K(523840K), 0.0714820 secs] 1633423K->1117613K(1834560K), 0.0718980 secs]
363489.713: [GC [1 CMS-initial-mark: 1117613K(1310720K)] 1301530K(1834560K), 0.2237580 secs]
363489.937: [CMS-concurrent-mark-start]
363495.025: [GC 363495.025: [ParNew: 523392K->0K(523840K), 0.0726450 secs] 1641005K->1125508K(1834560K), 0.0730750 secs]
363501.032: [GC 363501.032: [ParNew: 523392K->0K(523840K), 0.0828310 secs] 1648900K->1135299K(1834560K), 0.0833360 secs]
363506.197: [GC 363506.198: [ParNew: 523392K->0K(523840K), 0.0711940 secs] 1658691K->1141905K(1834560K), 0.0716800 secs]
363510.793: [GC 363510.793: [ParNew: 523392K->0K(523840K), 0.0986860 secs] 1665297K->1150247K(1834560K), 0.0992440 secs]
363514.765: [GC 363514.765: [ParNew: 523840K->0K(523840K), 0.2155430 secs] 1690628K->1263649K(1834560K), 0.2159440 secs]
363519.207: [CMS-concurrent-mark: 7.769/29.270 secs]
363519.207: [CMS-concurrent-preclean-start]
363519.729: [CMS-concurrent-preclean: 0.454/0.523 secs]
363519.729: [CMS-concurrent-abortable-preclean-start]
363521.051: [GC 363521.051: [ParNew: 523392K->523392K(523840K), 0.0000180 secs]363521.052: [CMS363521.104: [CMS-concurrent-abortable-preclean: 0.120/1.374 secs]
 (concurrent mode failure): 1263649K->900173K(1310720K), 8.5664420 secs] 1787041K->900173K(1834560K), 8.5671060 secs]
363531.417: [GC [1 CMS-initial-mark: 900173K(1310720K)] 1084069K(1834560K), 0.2132160 secs]



363419.049: [CMS-concurrent-sweep-start]
363420.908: [GC 363420.909: [ParNew: 523392K->0K(523840K), 0.0795650 secs] 1652124K->1136058K(1834560K), 0.0803380 secs]
363429.886: [GC 363429.887: [ParNew: 523392K->0K(523840K), 0.0706960 secs] 1659196K->1144335K(1834560K), 0.0714890 secs]
363432.566: [Full GC 363432.566: [ParNew: 520584K->0K(523840K), 0.0769280 secs] 1672290K->1169919K(1834560K), 0.0775740 secs]
363439.937: [Full GC 363439.938: [ParNew (promotion failed): 523840K->523840K(523840K), 0.3404490 secs] 1690606K->1712399K(1834560K), 0.3412880 secs]
363440.280: [GC 363440.280: [ParNew (promotion failed): 523840K->523840K(523840K), 0.2211610 secs]363440.502: [CMS363440.935: [CMS-concurrent-sweep: 4.549/21.886 secs]
 (concurrent mode failure): 1188559K->1047404K(1310720K), 9.2920010 secs] 1712399K->1047404K(1834560K), 9.5137760 secs]
363451.421: [GC [1 CMS-initial-mark: 1047404K(1310720K)] 1245963K(1834560K), 0.1440540 secs]
363453.521: [CMS-concurrent-mark-start]
363453.523: [GC 363453.523: [ParNew: 523840K->0K(523840K), 0.1876280 secs] 1576618K->1175643K(1834560K), 0.1879520 secs]
363458.913: [GC 363458.913: [ParNew: 523097K->0K(523840K), 0.0639300 secs] 1698741K->1181843K(1834560K), 0.0644500 secs]
363468.068: [GC 363468.068: [ParNew: 523392K->0K(523840K), 0.0758130 secs] 1705235K->1187900K(1834560K), 0.0763340 secs]
363472.286: [CMS-concurrent-mark: 6.721/18.765 secs]
363472.286: [CMS-concurrent-preclean-start]
363472.493: [CMS-concurrent-preclean: 0.182/0.207 secs]
363472.493: [CMS-concurrent-abortable-preclean-start]
363476.433: [GC 363476.433: [ParNew: 523392K->0K(523840K), 0.0798890 secs] 1711292K->1193725K(1834560K), 0.0804050 secs]
363485.438: [CMS-concurrent-abortable-preclean: 0.598/12.945 secs]
363485.440: [GC[YG occupancy: 268431 K (523840 K)]363485.441: [Rescan (parallel) , 0.3050930 secs]363485.746: [weak refs processing, 0.0183180 secs] [1 CMS-remark: 1193725K(1310720K)] 1462157K(1834560K), 0.3241100 secs]
363485.772: [CMS-concurrent-sweep-start]
363486.619: [CMS-concurrent-sweep: 0.847/0.847 secs]
363486.620: [CMS-concurrent-reset-start]
363486.665: [CMS-concurrent-reset: 0.046/0.046 secs]
363487.664: [GC 363487.664: [ParNew: 523392K->0K(523840K), 0.0714820 secs] 1633423K->1117613K(1834560K), 0.0718980 secs]
363489.713: [GC [1 CMS-initial-mark: 1117613K(1310720K)] 1301530K(1834560K), 0.2237580 secs]
363489.937: [CMS-concurrent-mark-start]
363495.025: [GC 363495.025: [ParNew: 523392K->0K(523840K), 0.0726450 secs] 1641005K->1125508K(1834560K), 0.0730750 secs]
363501.032: [GC 363501.032: [ParNew: 523392K->0K(523840K), 0.0828310 secs] 1648900K->1135299K(1834560K), 0.0833360 secs]
363506.197: [GC 363506.198: [ParNew: 523392K->0K(523840K), 0.0711940 secs] 1658691K->1141905K(1834560K), 0.0716800 secs]
363510.793: [GC 363510.793: [ParNew: 523392K->0K(523840K), 0.0986860 secs] 1665297K->1150247K(1834560K), 0.0992440 secs]
363514.765: [GC 363514.765: [ParNew: 523840K->0K(523840K), 0.2155430 secs] 1690628K->1263649K(1834560K), 0.2159440 secs]
363519.207: [CMS-concurrent-mark: 7.769/29.270 secs]
363519.207: [CMS-concurrent-preclean-start]
363519.729: [CMS-concurrent-preclean: 0.454/0.523 secs]
363519.729: [CMS-concurrent-abortable-preclean-start]
363521.051: [GC 363521.051: [ParNew: 523392K->523392K(523840K), 0.0000180 secs]363521.052: [CMS363521.104: [CMS-concurrent-abortable-preclean: 0.120/1.374 secs]
 (concurrent mode failure): 1263649K->900173K(1310720K), 8.5664420 secs] 1787041K->900173K(1834560K), 8.5671060 secs]
363531.417: [GC [1 CMS-initial-mark: 900173K(1310720K)] 1084069K(1834560K), 0.2132160 secs]
363531.631: [CMS-concurrent-mark-start]

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如果您无法升级到Java 7或6，您应该能够安装Java 5.0（更新22）的最后一个修补程序嗨，彼得，谢谢-需要一些澄清，那么更新22是否修复了CMS收集器中的一般问题，或者专门支持增量模式下的initiatingOccupancyFraction？我不知道，但自发布以来，已经有20多个更新，其中任何一个都可以解决这个问题。好的，谢谢…回到最初的问题，这些选项对于任何版本的JDK（5、6或7）都是合法的组合吗？JVM在启动时没有抱怨，但我没有发现任何说明InitiatingOccupancyFraction可以或不能在CMS增量模式下使用的文档。