I want to upgrade Percona Server for MySQL from 8.0.20 to 8.0.21. My server contains 3000 databases with 1000 tables in each database. Yes, I know this is a rare configuration. It is a bit like shared hosting.
After starting mysqld on the new version, I see in the log for about 20 minutes:
2020-11-25T18:27:27.571354Z 1 [System] [MY-011090] [Server] Data dictionary upgrading from version ‘80017’ to ‘80021’.
And then all the available memory and swap on the server ends, and finally the mysqld process was killed by OOM Killer.
Then everything starts all over again.
How can I upgrade a server with millions of tables?
I see issue in my test (1M tables,1000dbs with 1000 tables in each)) after upgrading from PS 8.0.20 to 8.0.21. Using SSD storage.
after upgrade 1st Startup in progress and with time it’s consuming more memory. I can see memory reducing on OS while Data dictionary upgrading from version ‘80017’ to ‘80021’. in progress.
I will test with upsteam as well and report this issue. I will update Bug# here later.