Swap being used when not necessary

Solution 1:

Do you have lot of stuff running on the server? If so, maybe consider a dedicated machine or VM for the DB.

Is this physical or VM/cloud server? Some cloud providers do NOT want you to use swap at all (so just putting that out there in case it is relevant): https://docs.rackspace.com/support/how-to/swap-space-on-cloud-servers/

There is some good discussion on this page for troubleshooting swap for MySQL or MariaDB -- maybe check the NUMA section toward the end: https://fromdual.com/do-not-underestimate-performance-impacts-of-swapping-on-numa-database-systems

This Q&A at MariaDB site leads to NUMA interleaving settings as a possible solution: https://mariadb.com/kb/en/swap-usage-wont-decrease/

A lot of discussion about memory and MariaDB: https://mariadb.com/kb/en/mariadb-memory-allocation/

And this is the authoritative youtube video for NUMA :-D https://youtu.be/KmtzQCSh6xk

Please upvote/accept this answer if it is helpful. Thanks.