jemalloc generating many files

问题

I followed the jemalloc instructions and setup the jemalloc on centOS 7. However, soon after setting

export LD_PRELOAD=/usr/local/lib/libjemalloc.so
export MALLOC_CONF=prof_leak:true,lg_prof_sample:50,lg_prof_interval:62,prof_final:true

environment variables, I could see a lot of jeprof.*.heap files being written to my current directory. I didn't start my jetty server at all, still, so many files are generated. Which process is generating it?

When I tried to start the application as follows

$LD_PRELOAD $MALLOC_CONF $JAVA_HOME/java/ Test

It resulted in Segmentation fault, but started writing many files continuously.

I tried to open a jeprof.*.heap like this

jeprof --show_bytes `which w` jeprof.47757.0.f.heap
top

this gave me 0 bytes. Tried to generate gif file even that file was empty. How can I fix this?

@apangin After your help and as described in the JVM_FindSignal function continuously allocates native memory post

I was able to get the below details

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

But I don't see any my JNI class names from .so file. I could see many memory addresses. Am I missing anything or the symbols are not resolved correctly?

Thanks Raj

回答1:

When you export LD_PRELOAD environment variable, jemalloc library gets loaded into every single process you run, including every bash command.

If you want to apply it only to Java process, use

LD_PRELOAD=/usr/local/lib/libjemalloc.so $JAVA_HOME/bin/java Test

i.e. set the variable (without export) right before the java command.

来源：https://stackoverflow.com/questions/59905765/jemalloc-generating-many-files

标签

memory-leaks

jvm

java-native-interface

centos7

jemalloc