I've been trying it out on solr 3.6.1 with a 32GB heap and G1GC seems to be
more prone to OOMEs than CMS. I have been running it on one slave box in our
farm and the rest of the slaves are still on CMS and three times now it has
gone OOM on me whereas the rest of our slaves kept chugging along with no
errors. I even went from no other tuning params to using these suggested on
Shawns wiki page here and that didn't help either, still got some OOMs. I'm
giving it a 'fail' pretty soon here.
-XX:+AggressiveOpts -XX:+HeapDumpOnOutOfMemoryError
-XX:+OptimizeStringConcat -XX:+UseFastAccessorMethods
-XX:+UseG1GC -XX:+UseStringCache -XX:-UseSplitVerifier
-XX:MaxGCPauseMillis=50
http://wiki.apache.org/solr/ShawnHeisey#GC_Tuning
Thanks
Robi
-----Original Message-----
From: Timothy Potter [mailto:thelabd...@gmail.com]
Sent: Thursday, June 20, 2013 9:22 AM
To: solr-user@lucene.apache.org
Subject: Re: Informal poll on running Solr 4 on Java 7 with G1GC
Awesome info, thanks Shawn! I'll post back my results with G1 after we've had
some time to analyze it in production.
On Thu, Jun 20, 2013 at 11:01 AM, Shawn Heisey <s...@elyograg.org> wrote:
> On 6/20/2013 8:02 AM, John Nielsen wrote:
>>
>> We used to use G1, but recently went back to CMS.
>>
>> G1 gave us too long stop-the-world events. CMS uses more ressources
>> for the same work, but it is more predictable and we get better
>> worst-case performance out of it.
>
>
> This is exactly the behavior I saw. When you take a look at the
> overall stats and the memory graph over time, G1 looks way better.
> Unfortunately GC with any collector does sometimes get bad, and when
> that happens, un-tuned
> G1 is a little worse than un-tuned CMS. Perhaps if G1 were tuned, it
> would be really good, but I haven't been able to find any information
> on how to tune G1.
>
> jHiccup or gclogviewer can give you really good insight into how your
> GC is doing in both average and worst-case scenarios. jHiccup is a
> wrapper for your program and gclogviewer draws graphs from GC logs.
> I'm not sure whether gclogviewer works with G1 logs or not, but I know
> that jHiccup will work with G1.
>
> http://www.azulsystems.com/downloads/jHiccup
> http://code.google.com/p/gclogviewer/downloads/list
> http://code.google.com/p/gclogviewer/source/checkout
> http://code.google.com/p/gclogviewer/issues/detail?id=7
>
> Thanks,
> Shawn
>
