I am running galera cluster (mariadb) with 2 nodes. We had one very large history table that I dropped and recreated only the structure for it from a mysqldump ever since then the database has been getting more and more sluggish.
Do I need to reboot my sql server cluster? Is the RAM still populated with history table data?
thanks
It would probably have been faster to do TRUNCATE TABLE. This would keep the structure but remove the data.
DROP TABLE has a delayed overhead on most Operating Systems. The OS spends some time freeing up the pieces of the file that represents that table. For 'small' tables this effort goes unnoticed. For a huge table, it may take minutes.
As for "more and more" sluggish, this could be a compounding of things being slowed down, then interfering with each other. Did you also note a large rise in Threads_running?
You may need to keep an eye on the slowlog to see what queries are sensitive to this kind of interference. Then work on speeding up the slowest.