Garbage collection

[former_member240124]

Hi,

How to trigger GC manually in Java using Telnet?

When i give the command msc, i dont get any output. I get a message saying command not found.

Kindly help me on this.

Thanks & Best Regards,

Rengan

[Vlado]

Hi Rengan,

Maybe because the command is GC.

Where did you find this MSC?

HTH!

-Vladimir

[former_member240124]

If i enter GC command then a gc should occur and gc.log file should be updated with new values?

If answer to the above question is YES, then that is not happening.

Thanks & Best Regards,

Rengan

[Vlado]

Hi Rengan,

If you execute the GC command a GC does occur but the logs go to /usr/sap/<SID>/<JCxx>/work/std_server0.out.

HTH!

-Vladimir

[former_member240124]

HI Vladmir,

I trired the command but could not find the logs in std_server0.out.

Is it different for double stack (ABAP + J2EE) system.

Thanks & Best Regards,

Rengan

[Vlado]

Do you see in telnet sth like:

<i>[Shell -> GC] Garbage collector run.</i>

I'm pretty sure it goes into std_server0.out on double stack systems as well, but you can search in the whole work dir just to make sure.

-Vladimir

[former_member240124]

Hi Vladimir,

I tried again, but no log entries in std_server0.out file

Any other options??

Thanks & Best Regards,

Rengan

[Vlado]

I can definitely see GC traces in std_server0.out.

Do you get in the telnet console <i>[Shell -> GC] Garbage collector run</i> ?

[former_member240124]

Yes i could see [Shell -> GC] Garbage collector run in command prompt.

BUt log is missing

[Vlado]

OK, probably you have the <b>-XX:+DisableExplicitGC</b> java parameter set for your server. Remove it in Config Tool, restart the cluster and try again.

-Vladimir

[Former Member]

/people/david.rutt/blog/2006/08/23/trouble-shooting-java-memory-dumpster-diving

Go here. This should clear some things up.