As James mentioned it really depends on how many jobs you have and what
you are actually building, project size etc. Off the top of my head here
are some tips:
If you do not require more than 2GB on Windows or 3GB on Linux I
recommend using a 32-bit JVM (64-bit JVM uses double the space for every
pointer), if 32-bit JVM is not an option you may be interested in
investigating the CompressedOops JVM switch [1].
Enable the com.sun.management.jmxremote JVM switch and connect to your
JVMs with VisualVM [2]. Doing so will allow you to monitor how much heap
and perm gen your JVM is occupying, from this it should be straight
forward to tune the values.
Cheers,
Johno
[1] https://wikis.oracle.com/display/HotSpotInternals/CompressedOops
[2] http://visualvm.java.net/
On 7/01/2013 7:36 PM, Jeff wrote:
Thanks...I unfortunately can't be in the UK for the event.
So if the amount of RAM is fixed (4GB), what is a good rule of thumb
for determining what to allocate to the slave process, how many
executors it can reasonably support, etc?
I realize there are a lot of other variables but any starting point
and things to consider or factor in that may not be obvious could help.
Or is it just a matter or monitoring and tuning?
On Jan 7, 2013 2:31 AM, "Nord, James" <jn...@nds.com
<mailto:jn...@nds.com>> wrote:
Have enough RAM on the slave that you can run your jobs plus
Jenkins + some for overhead.
(e.g. 1GB of Jenkins slave, + #executors * ( 2GB for Maven +2GB
for unit tests in forked VM) + OS overhead)
Although this amount is mostly an overkill setting it too close
to the threshold will slow your jobs down due to paging at best,
or mean you get intermittent failures due to OOM at worst –
(memory is generally cheaper that human time taken to investigate
issues!) (our maven jobs can be very memory hungry so your
figures will vary) (Note I recommend a single executor per slave)
The master depends more on how many jobs / reports per jobs / job
history you have etc – we use 10GB (but not tomcat).
If you’re in the UK and there is any spaces left I will cover some
things like this next week at the Jenkins User Event.
/James
*From:*jenkinsci-users@googlegroups.com
<mailto:jenkinsci-users@googlegroups.com>
[mailto:jenkinsci-users@googlegroups.com
<mailto:jenkinsci-users@googlegroups.com>] *On Behalf Of *Jeff
*Sent:* 04 January 2013 21:56
*To:* jenkinsci-users@googlegroups.com
<mailto:jenkinsci-users@googlegroups.com>
*Subject:* Master + slave + job JVM memory tuning...
I'm trying to optimize how much memory I allocate to the master
application (aka - tomcat), slave processes, maven tasks, etc. and
going crazy.
I've been unsuccessful in finding a guideline to determine how
much memory I ought to allocate or if I should just let the
defaults work.
All machines are single processor, dual core with 4 GB ram.
I've typically set tomcat to use 2048MB + 512MB permgen space and
set my maven process to use 384MB max. Is this reasonable?
My slaves are set to run 4 executors. Jobs use either svn or git
to check out code and Maven to build with a SONAR post-build
analysis. We also do Maven releases at times.
How much does the core slave process need? Is there a
"rule-of-thumb" based on the number of executors?
Any perspective/considerations/resources/links/pointers are much
appreciated.
--
Jeff Vincent
predato...@gmail.com <mailto:predato...@gmail.com>
See my LinkedIn profile at:
http://www.linkedin.com/in/rjeffreyvincent
I ♥ DropBox <http://db.tt/9O6LfBX> !!
------------------------------------------------------------------------
**************************************************************************************
This message is confidential and intended only for the addressee.
If you have received this message in error, please immediately
notify the postmas...@nds.com <mailto:postmas...@nds.com> and
delete it from your system as well as any copies. The content of
e-mails as well as traffic data may be monitored by NDS for
employment and security purposes. To protect the environment
please do not print this e-mail unless necessary.
NDS Limited. Registered Office: One London Road, Staines,
Middlesex, TW18 4EX, United Kingdom. A company registered in
England and Wales. Registered no. 3080780. VAT no. GB 603 8808 40-00
**************************************************************************************
--
:: Johnathan Crawford
:: Senior Software Developer
Sulake | Porkkalankatu 1 | 00180 Helsinki, Finland
http://www.sulake.com | tel +358 10 656 7000 | fax +358 10 656 7010
--
You received this message because you are subscribed to the Google Groups "Jenkins
Users" group.
To unsubscribe from this group and stop receiving emails from it, send an email
to jenkinsci-users+unsubscr...@googlegroups.com.
For more options, visit https://groups.google.com/groups/opt_out.
