了解Jeprofile输出 [英] Understanding Jeprofile output

问题描述

我能够根据此处 jemalloc帖子

请找到jemalloc输出和图形.

Please find the jemalloc output and the graph.

> Using local file /bin/java. Using local file jeprof.57473.0.f.heap.
> Total: 79372091 B 78084060  98.4%  98.4% 78084060  98.4%
> je_prof_backtrace  1288031   1.6% 100.0%  1474342   1.9%
> Java_java_util_zip_ZipFile_getZipMessage
>        0   0.0% 100.0%  6889972   8.7% 0x00007f3d5ebac3e6
>        0   0.0% 100.0%   270421   0.3% 0x00007f3d5ebb8a79
>        0   0.0% 100.0%   727762   0.9% 0x00007f3d5ebb8a87
>        0   0.0% 100.0%   589239   0.7% 0x00007f3d5ebb9ab2
>        0   0.0% 100.0%   854269   1.1% 0x00007f3d5ebb9ac0
>        0   0.0% 100.0%   270421   0.3% 0x00007f3d5ebb9cb7
>        0   0.0% 100.0%   135210   0.2% 0x00007f3d5ebbc5fa
>        0   0.0% 100.0%   135210   0.2% 0x00007f3d5ebbc768
>        0   0.0% 100.0%   135210   0.2% 0x00007f3d5ee57146
>        0   0.0% 100.0%   143743   0.2% 0x00007f3d5ee8bc25
>        0   0.0% 100.0%   444413   0.6% 0x00007f3d5ef13945
>        0   0.0% 100.0%   136258   0.2% 0x00007f3d5ef764fb
>        0   0.0% 100.0%  8463202  10.7% 0x00007f3d5efbdb8a
>        0   0.0% 100.0%   143743   0.2% 0x00007f3d5f220c67
>        0   0.0% 100.0%   135210   0.2% 0x00007f3d5f3a5c65
>        0   0.0% 100.0% 55473738  69.9% AsyncGetCallTrace
>        0   0.0% 100.0% 48103708  60.6% JLI_GetStdArgc
>        0   0.0% 100.0% 48103708  60.6% JNI_CreateJavaVM
>        0   0.0% 100.0% 11897251  15.0% JNI_GetCreatedJavaVMs
>        0   0.0% 100.0% 11897251  15.0% JVM_DefineClassWithSource
>        0   0.0% 100.0%   271469   0.3% JVM_FindClassFromBootLoader
>        0   0.0% 100.0%   431486   0.5% JVM_FindClassFromCaller
>        0   0.0% 100.0%   131120   0.2% JVM_FindLoadedClass
>        0   0.0% 100.0% 76994237  97.0% JVM_FindSignal
>        0   0.0% 100.0%   148137   0.2% JVM_GetCPMethodClassNameUTF
>        0   0.0% 100.0%   148137   0.2% JVM_GetCPMethodSignatureUTF
>        0   0.0% 100.0%   135210   0.2% JVM_GetClassDeclaredFields
>        0   0.0% 100.0%   405631   0.5% JVM_GetClassName
>        0   0.0% 100.0%   143743   0.2% JVM_IHashCode
>        0   0.0% 100.0%   143743   0.2% JVM_MonitorWait
>        0   0.0% 100.0%   431486   0.5% JVM_RawMonitorExit
>        0   0.0% 100.0%   659324   0.8% JVM_StartThread
>        0   0.0% 100.0% 77220036  97.3% JVM_handle_linux_signal
>        0   0.0% 100.0% 11897251  15.0% Java_java_lang_ClassLoader_defineClass1
>        0   0.0% 100.0%   271469   0.3% Java_java_lang_ClassLoader_findBootstrapClass
>        0   0.0% 100.0%   431486   0.5% Java_java_lang_Class_forName0
>        0   0.0% 100.0%   592551   0.7% Java_java_util_zip_Inflater_inflateBytes
>        0   0.0% 100.0%   134688   0.2% Java_java_util_zip_Inflater_init
>        0   0.0% 100.0%  1117359   1.4% Java_java_util_zip_ZipFile_open
>        0   0.0% 100.0% 75438262  95.0% SUNWprivate_1.1
>        0   0.0% 100.0%   296275   0.4% VerifyClassForMajorVersion
>        0   0.0% 100.0%   356982   0.4% ZIP_Open
>        0   0.0% 100.0%  1474342   1.9% ZIP_Unlock
>        0   0.0% 100.0%   176271   0.2% _GLOBAL__sub_I_eh_alloc.cc
>        0   0.0% 100.0%   176271   0.2% _GLOBAL__sub_I_eh_alloc.cc (inline)
>        0   0.0% 100.0% 59721527  75.2% __clone
>        0   0.0% 100.0%   176271   0.2% __static_initialization_and_destruction_0 (inline)
>        0   0.0% 100.0%   176271   0.2% _dl_init_internal
>        0   0.0% 100.0%   176271   0.2% _dl_start_user
>        0   0.0% 100.0%   131184   0.2% fork1
>        0   0.0% 100.0% 78084060  98.4% imalloc (inline)
>        0   0.0% 100.0% 78084060  98.4% imalloc_body (inline)
>        0   0.0% 100.0%   592551   0.7% inflate
>        0   0.0% 100.0%   592551   0.7% inflateBackEnd
>        0   0.0% 100.0%   134688   0.2% inflateInit2_
>        0   0.0% 100.0% 78084060  98.4% je_malloc_default
>        0   0.0% 100.0% 78084060  98.4% prof_alloc_prep (inline)
>        0   0.0% 100.0% 59721527  75.2% start_thread

该图也已附加

需要一些帮助来了解问题出在哪里吗?

Need some help in understanding where the problem is?

环境是: Centos 7 Java 1.8.0 海湾合作委员会9

Enviornment is: Centos 7 Java 1.8.0 GCC 9

谢谢！

推荐答案

1. 在jemalloc输出中，JVM_FindSignal占分配的97％.这是不正确的，因为JVM_FindSignal不分配任何东西.

1. In your jemalloc output, JVM_FindSignal is accounted for 97% of allocations. This can't be true, since JVM_FindSignal does not allocate anything.

这必须是 JVM没有调试符号的问题的结果.按照此答案中的说明安装带有JDK调试符号的软件包，或将JDK与内置调试符号一起使用，例如 Liberica JDK .

This must be the result of the issue that JVM has no debug symbols. Install the package with JDK debug symbols as descibed in this answer, or use JDK with built-in debug symbols, e.g. Liberica JDK.

jemalloc对Java方法一无所知.它无法将JIT编译代码中的地址转换为Java方法名称.因此，您的jemalloc输出中有这么多地址(十六进制数字).

jemalloc does not know anything about Java methods. It can't translate the addresses in JIT compiled code to Java method names. Hence so many addresses (hex numbers) in your jemalloc output.

有一个Java分析器 async-profiler 可以跟踪本机内存分配到Java代码，并将Java堆栈跟踪显示为Flame Graphs.使用async-profiler对malloc，mprotect和mmap调用进行概要分析有助于发现本机内存泄漏.有关详细信息，请参见此答案.

There is a Java profiler, async-profiler, that can trace native memory allocations down to Java code, and show Java stack traces as Flame Graphs. Profiling malloc, mprotect and mmap calls with async-profiler can be helpful in finding native memory leaks. See this answer for details.

有一个演示视频展示了一个使用jemalloc和async分析本机分配的示例-profiler.

There is a presentation video showing an example of profiling native allocations with both jemalloc and async-profiler.

这篇关于了解Jeprofile输出的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！