Hi Duo, on bigger machines( aka >64/128 GB RAM, enough CPU resource) what would be the preferred way to approach this topic? 1. bigger heap, generational ZGC Java21, block cache and memstore on heap OR 2. just enough heap, G1GC, off heap bucket cache and off heap memstore.
Thanks! On Fri, Aug 29, 2025 at 3:05 PM 张铎(Duo Zhang) <palomino...@gmail.com> wrote: > HBase sometimes has very large pressure on heap, so ZGC in java 17 may > not be a good choice unless you are sure that your cluster will not > have very heavy load. G1GC in java 17 is good enough for most cases. > > If you want to use ZGC, better to use JAVA 21 where ZGC is generational. > > Thanks. > > > Adam Sjøgren <a...@novonesis.com.invalid> 于2025年8月29日周五 19:07写道： > > > > Hi Atanas, > > > > > > Atanas writes: > > > > > We run Hbase 2.5.12 with Java17. We use a rather small heap size, > because > > > we rely on off heap read(bucket cache) and off heap write paths. > > > Apart from the defaults our hbase-env.sh contains just the very basics > for > > > G1GC > > > export HBASE_REGIONSERVER_OPTS="-XX:+UseG1GC -XX:MaxGCPauseMillis=50 \ > > > -Xms4G -Xmx4G \ > > > $HBASE_REGIONSERVER_OPTS" > > > > > > and also "export HBASE_OFFHEAPSIZE" in our case. > > > > Thanks for the input - it's nice to know that Java 17 is in use. > > > > For Solr we're using ZGC, as it was recommended on the mailinglist: > > > > # Recommended on Solr users mailing list ( > https://lists.apache.org/thread/bcq6rdzv66m7hsnn346kzjl5qt2pxv9s): > > GC_TUNE=" \ > > -XX:+UnlockExperimentalVMOptions \ > > -XX:+UseZGC \ > > -XX:+ParallelRefProcEnabled \ > > -XX:+ExplicitGCInvokesConcurrent \ > > -XX:+UseStringDeduplication \ > > -XX:+AlwaysPreTouch \ > > -XX:+UseNUMA \ > > " > > > > I'm not well-versed in Java, so I don't know what to think :-) > > > > > > Best regards, > > > > Adam > > > > -- > > "No more than that, but very powerful all the Adam > Sjøgren > > same; simple things are good." > a...@novonesis.com > > > -- [image: NOTO] <https://notolytix.com/> Atanas Dimitrov *Senior DevOps* m: +359 888 675769 e: atanas.dimit...@noto360.com w: notolytix.com [image: LinkedIn] <https://www.linkedin.com/company/notolytix-ltd/> [image: Twitter] <https://twitter.com/notolytix> [image: Facebook] <https://facebook.com/notolytix/> [image: YouTube] <https://www.youtube.com/playlist?list=PL73ML6RUXLXntd-M5umOnt_1frPiH8aFt>
