Can you say something about the root cause for solr processes to crash? Are they killed by Linux? Which version of Java did you run on 18.04? Other changes done at the same time, such as OS-level settings for ulimits, vm.max_map_count, swappiness etc.
If you have not fine-tuned your JVM settings, it is recommended to run with the default JVM/GC settings. G1 in latest Java-11 shoud be fine. Jan > 26. jan. 2023 kl. 14:26 skrev Adam Sjøgren <a...@koldfront.dk.INVALID>: > > Hi, > > > We have a Solr Cloud cluster running 8.11.2 on 16 servers that have just > been upgraded to Ubuntu 20.04 (from 18.04). > > It looks like we are getting shards down/recovering more often than > previously, so I'm wondering what version of Java and which garbage > collector is recommended on Ubuntu 20.04? > > On https://solr.apache.org/docs/8_11_2/SYSTEM_REQUIREMENTS.html is says > Java 8 or higher - we are running 11.0.17+8-1ubuntu2~20.04. > > That page also links to > https://cwiki.apache.org/confluence/display/lucene/JavaBugs which very > clearly says not to use the G1 garbage collector and that the page isn't > outdated. Hm. > > > Best regards, > > Adam > > -- > "The laws of perspective have been repealed! Adam Sjøgren > Objects no longer diminish in size with distance!" a...@koldfront.dk >
