Hello, for testing the upgrade path I did an in-place slave server (with optimistic parallel replication) upgrade from 10.4.26 to 10.6.11, but the performance difference is so significant/abysmal I don't even know where to look at (see the attached QPS chart before and after upgrade - it's like 2-3x times lower!). All the previous settings/configuration are kept. I have various server parameters monitored but none seem to indicate why would everything become way slower (see for example the disk write operations also are 2-3 times lower). Maybe someone can give an idea where to look or what to check what could make such an impact? p.s. I know about https://jira.mariadb.org/browse/MDEV-29988 but I don't think that I'm hitting it since the cpu load hasn't changed (is even lower). wbr rr