On 2/6/23 17:15, Wei wrote:
Do you see ZGC having better query performance than G1? We are migrating from Solr 8 / JDK 11/ G1 to Solr 9 with JDK 17 / G1. Also are there any notable performance changes from 9.0.0 to the latest 9.1.1?
I don't have enough information available to answer the last question. I don't really have access to Solr installs any more except my tiny little personal install. One node, 200K docs, 800MB index size. I've got it running with a 1GB heap, which is much bigger than it needs.
ZGC's individual pauses are VERY short compared to G1, but it does a lot more collections. I don't have GC logs for detailed comparison any more, but if I recall correctly, the total time spent in GC was less for ZGC compared to G1. General latency would be better, but I don't see it doing a lot for the speed of an individual query.
I can say for sure that on my tiny install, indexing is a little bit slower with ZGC. I suspect that in a setup doing highly threaded indexing, that it probably wouldn't be substantially affected and might be faster than G1. My indexing with dovecot is mostly single-threaded. It does index multiple mailboxes simultaneously, but the vast majority of the messages are in one mailbox (mine).
Thanks, Shawn
