error while trying to access java program

[rsff]

so while trying to use ttop I get a error strange thing is that jps detects it...

thanks
RF

rferreira@graylog1-cab2:~$ sudo java -jar sjk-plus-0.4.2.jar jps
25987   sjk-plus-0.4.2.jar jps
23691   /usr/share/graylog-server/graylog.jar server -f /etc/graylog/server/server.conf -np
rferreira@graylog1-cab2:~$ sudo java -jar sjk-plus-0.4.2.jar ttop -p 23691 -n 20 -o CPU
Failed to access MBean server: 23691

[aragozin]

Hi,

-X option can be used to enable detailed stack traces.
Do JDK tools such as jstack or jmap can access that process process?

[rsff]

heya,
thanks for the response with jstat i can access it... and also jmap

rferreira@graylog1-cab2:~$ sudo jstat -gccause 30295 2000
  S0     S1     E      O      M     CCS    YGC     YGCT    FGC    FGCT     GCT    LGCC                 GCC
 43.56  46.08 100.00  17.42  97.70  95.81     53   10.782     2    0.606   11.388 Allocation Failure   Allocation Failure
  0.00  35.54  18.89  17.74  97.71  95.81     55   11.330     2    0.606   11.936 Allocation Failure   No GC
^Crferreira@graylog1-cab2:~sudo java -jar sjk-plus-0.4.2.jar ttop -p 30295 --verbose
Failed to access MBean server: 30295

rferreira@graylog1-cab2:~$ sudo jmap 30295
Attaching to process ID 30295, please wait...
Debugger attached successfully.
Server compiler detected.
JVM version is 25.91-b14
0x0000000000400000      7K      /usr/lib/jvm/java-8-oracle/jre/bin/java
0x00007fa525fb7000      88K     /lib/x86_64-linux-gnu/libgcc_s.so.1
0x00007fa5261cd000      250K    /usr/lib/jvm/java-8-oracle/jre/lib/amd64/libsunec.so
0x00007fa527ec9000      240K    /usr/share/graylog-server/lib/sigar/libsigar-amd64-linux.so
0x00007fa57c81f000      90K     /usr/lib/jvm/java-8-oracle/jre/lib/amd64/libnio.so
0x00007fa57cf1f000      113K    /usr/lib/jvm/java-8-oracle/jre/lib/amd64/libnet.so
0x00007fa57d136000      49K     /usr/lib/jvm/java-8-oracle/jre/lib/amd64/libmanagement.so
0x00007fa632b5a000      121K    /usr/lib/jvm/java-8-oracle/jre/lib/amd64/libzip.so
0x00007fa632d75000      42K     /lib/x86_64-linux-gnu/libnss_files-2.19.so
0x00007fa632f80000      46K     /lib/x86_64-linux-gnu/libnss_nis-2.19.so
0x00007fa63318c000      95K     /lib/x86_64-linux-gnu/libnsl-2.19.so
0x00007fa6333a6000      38K     /lib/x86_64-linux-gnu/libnss_compat-2.19.so
0x00007fa6335b0000      220K    /usr/lib/jvm/java-8-oracle/jre/lib/amd64/libjava.so
0x00007fa6337dc000      64K     /usr/lib/jvm/java-8-oracle/jre/lib/amd64/libverify.so
0x00007fa6339eb000      31K     /lib/x86_64-linux-gnu/librt-2.19.so
0x00007fa633bf3000      1046K   /lib/x86_64-linux-gnu/libm-2.19.so
0x00007fa633ef9000      16529K  /usr/lib/jvm/java-8-oracle/jre/lib/amd64/server/libjvm.so
0x00007fa634edc000      1797K   /lib/x86_64-linux-gnu/libc-2.19.so
0x00007fa6352a1000      14K     /lib/x86_64-linux-gnu/libdl-2.19.so
0x00007fa6354a5000      99K     /usr/lib/jvm/java-8-oracle/jre/lib/amd64/jli/libjli.so
0x00007fa6356bb000      138K    /lib/x86_64-linux-gnu/libpthread-2.19.so
0x00007fa6358d9000      145K    /lib/x86_64-linux-gnu/ld-2.19.so

[aragozin]

Have you tries -X option of SJK ?
jstat is using mmapped file to get stats, so it would work event if JVM is defunt
jmap in your example is also using non-colaborative way to access JVM data (via platform debugger)

Does jstack work for this process?

[rsff]

Heya ,
yeah I tried the option -X in the SJK same output:

rferreira@graylog1-cab2:~$ sudo java -jar sjk-plus-0.4.2.jar ttop -p 30295 -X
Failed to access MBean server: 30295

regarding jstack:

rferreira@graylog1-cab2:~$ sudo jstack 30295
30295: Unable to open socket file: target process not responding or HotSpot VM not loaded
The -F option can be used when the target process is not responding

but when passing the -F flag I can access it..

[aragozin]

jstack -F using non-colaborative approach. jstack (without -F) using same interface as sjk - JVM attach attach protocol.

Does problem remain after graylog restart?

What is working directory for target JVM? Does target JVM run under root?

[rsff]

heya,
the problem persists even after graylog restart.

the jvm runs under the user graylog

rferreira@graylog1-cab2:~$ ps -ef |grep java

graylog  30295     1 99 18:55 ?        10:43:30 /usr/bin/java -Xms30g -Xmx30g -XX:NewRatio=2 -server -XX:+ResizeTLAB -XX:+UseConcMarkSweepGC -XX:+UseParNewGC -XX:+DisableExplicitGC -XX:+UseCMSInitiatingOccupancyOnly -XX:+CMSClassUnloadingEnabled -XX:+CMSScavengeBeforeRemark -XX:CMSInitiatingOccupancyFraction=33 -XX:-OmitStackTraceInFastThrow -XX:+UseGCLogFileRotation -XX:NumberOfGCLogFiles=5 -XX:GCLogFileSize=1m -Xloggc:/tmp/memoryGC.log -XX:+PrintGCDetails -XX:+PrintGCDateStamps -XX:+PrintGCTimeStamps -XX:+PrintHeapAtGC -XX:+PrintTenuringDistribution -jar -Dlog4j.configurationFile=file:///etc/graylog/server/log4j2.xml -Djava.library.path=/usr/share/graylog-server/lib/sigar -Dgraylog2.installation_source=deb /usr/share/graylog-server/graylog.jar server -f /etc/graylog/server/server.conf -np

[aragozin]

You should run sjk under same user as target process.
Could you try sudo -u graylog jstack PID ? If it would work it should work for sjk too.

[rsff]

sudo -u graylog java -jar sjk-plus-0.4.2.jar ttop -p 30295
Monitoring threads ...

great sucess thanks!