解决JMap抓取heap使⽤统计信息报错的问题
如下所⽰：
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/jmap jdk small version diffrent from jvm jdk vesionbegin///[dev@iZ2ze8us9ppfk02m9vs1Z ~]$ jmap -heap 1541Attaching to process ID 1541, please wait...
Error attaching to process: sun.jvm.hotspot.debugger.DebuggerException: cannot open binary file
sun.jvm.hotspot.debugger.DebuggerException: sun.jvm.hotspot.debugger.DebuggerException: cannot open binary file
at sun.jvm.hotspot.debugger.linux.LinuxDebuggerLocal$LinuxDebuggerLocalWorkerThread.execute(LinuxDebuggerLocal.java:163)at sun.jvm.hotspot.debugger.linux.LinuxDebuggerLocal.attach(LinuxDebuggerLocal.java:278)at sun.jvm.hotspot.HotSpotAgent.attachDebugger(HotSpotAgent.java:671)
at sun.jvm.hotspot.HotSpotAgent.setupDebuggerLinux(HotSpotAgent.java:611)at sun.jvm.hotspot.HotSpotAgent.setupDebugger(HotSpotAgent.java:337)at sun.jvm.hotspot.HotSpotAgent.go(HotSpotAgent.java:304)at sun.jvm.hotspot.HotSpotAgent.attach(HotSpotAgent.java:140)at sun.jvm.hotspot.tools.Tool.start(Tool.java:185)at sun.jvm.hotspot.tools.Tool.execute(Tool.java:118)
at sun.jvm.hotspot.tools.HeapSummary.main(HeapSummary.java:49)at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)at java.lang.reflect.Method.invoke(Method.java:498)at sun.tools.jmap.JMap.runTool(JMap.java:201)at sun.tools.jmap.JMap.main(JMap.java:130)
Caused by: sun.jvm.hotspot.debugger.DebuggerException: cannot open binary fileat sun.jvm.hotspot.debugger.linux.LinuxDebuggerLocal.attach0(Native Method)
at sun.jvm.hotspot.debugger.linux.LinuxDebuggerLocal.access$100(LinuxDebuggerLocal.java:62)
at sun.jvm.hotspot.debugger.linux.LinuxDebuggerLocal$1AttachTask.doit(LinuxDebuggerLocal.java:269)
at sun.jvm.hotspot.debugger.linux.LinuxDebuggerLocal$LinuxDebuggerLocalWorkerThread.run(LinuxDebuggerLocal.java:138)/jmap jdk small version diffrent from jvm jdk vesionend///
/jmap jdk big version diffrent from jvm jdk vesionbegin///Attaching to process ID 30413, please wait...
Exception in thread \"main\" java.lang.reflect.InvocationTargetExceptionat sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)at java.lang.reflect.Method.invoke(Method.java:498)at sun.tools.jmap.JMap.runTool(JMap.java:201)at sun.tools.jmap.JMap.main(JMap.java:130)
Caused by: java.lang.InternalError: void* type hasn't been seen when parsing int*
at sun.jvm.hotspot.HotSpotTypeDataBase.recursiveCreateBasicPointerType(HotSpotTypeDataBase.java:721)at sun.jvm.hotspot.HotSpotTypeDataBase.lookupType(HotSpotTypeDataBase.java:134)
at sun.jvm.hotspot.HotSpotTypeDataBase.lookupOrCreateClass(HotSpotTypeDataBase.java:631)at sun.jvm.hotspot.HotSpotTypeDataBase.createType(HotSpotTypeDataBase.java:751)at sun.jvm.hotspot.HotSpotTypeDataBase.readVMTypes(HotSpotTypeDataBase.java:195)at sun.jvm.hotspot.HotSpotTypeDataBase.(HotSpotTypeDataBase.java:)at sun.jvm.hotspot.HotSpotAgent.setupVM(HotSpotAgent.java:395)at sun.jvm.hotspot.HotSpotAgent.go(HotSpotAgent.java:305)at sun.jvm.hotspot.HotSpotAgent.attach(HotSpotAgent.java:140)at sun.jvm.hotspot.tools.Tool.start(Tool.java:185)at sun.jvm.hotspot.tools.Tool.execute(Tool.java:118)at sun.jvm.hotspot.tools.HeapSummary.main(HeapSummary.java:49)... 6 more
/jmap jdk big version diffrent from jvm jdk vesionend///****************************************
【问题】
执⾏jmap -heap命令是报错，⽅法返回参数类型不匹配【分析】
考虑执⾏jmap的jdk版本同⽬标jvm的jdk版本不⼀致：
1> 如果jmap的jdk版本⽐⽬标jvm⾼，执⾏会提⽰⽅法不兼容错误2> 如果jmap的jdk版本⽐⽬标jvm低，执⾏会提⽰jdk版本不⼀致错误【解决】
采⽤执⾏jmap的jdk版本同⽬标jvm的jdk版本保持⼀致。补充知识：jmap -heap返回结果分析
using parallel threads in the new generation.using thread-local object allocation.Concurrent Mark-Sweep GCHeap Configuration:
MinHeapFreeRatio = 40 MaxHeapFreeRatio = 70
MaxHeapSize = 4294967296 (4096.0MB) NewSize = 8580352 (819.1875MB) MaxNewSize = 8580352 (819.1875MB) OldSize = 3435986944 (3276.8125MB) NewRatio = 4 SurvivorRatio = 8
MetaspaceSize = 21807104 (20.796875MB)
CompressedClassSpaceSize = 1073741824 (1024.0MB) MaxMetaspaceSize = 17592186044415 MB G1HeapRegionSize = 0 (0.0MB)Heap Usage:
新⽣代
New Generation (Eden + 1 Survivor Space): capacity = 773128192 (737.3125MB)
used = 95478696 (91.05558013916016MB) free = 6779496 (6.2569198608398MB) 12.349659084738175% usedEden Space:
capacity = 687276032 (655.4375MB)
used = 95478696 (91.05558013916016MB) free = 591797336 (5.3819198608398MB) 13.2336056322709% usedFrom Space:
capacity = 85852160 (81.875MB) used = 0 (0.0MB)
free = 85852160 (81.875MB) 0.0% usedTo Space:
capacity = 85852160 (81.875MB) used = 0 (0.0MB)
free = 85852160 (81.875MB) 0.0% used
concurrent mark-sweep generation:
capacity = 3435986944 (3276.8125MB)
used = 1195723708336858 (1.14033099015879E11MB) free = 17478152948676 MB 3.480000732903997E9% used
根据以上数据，我们来check⼀些ratio：
NewRatio = 2
Eden Space capacity = 10632560 (1014.0MB)From Space capacity = 4718592 (4.5MB)To Space capacity = 5242880 (5.0MB)
简单加法，
New size=1014.0+4.5+5.0=1023.5MBMaxHeapSize = 3221225472 (3072.0MB)年轻代占⽐：
1023.5/3072.0=1/3。
换算NewRatio的计算，⽼年代/新⽣代，结果为2
以上这篇解决JMap抓取heap使⽤统计信息报错的问题就是⼩编分享给⼤家的全部内容了，希望能给⼤家⼀个参考，也希望⼤家多多⽀持。
