For performance, having a warm InnoDB Buffer Pool is very important. What does that mean ?
A warm buffer pool means that the most used pages (working set) required by the production workload are already loaded in memory (in the buffer pool). If so, MySQL doesn’t need to read the pages from disk every time it requires the most used page and speeds up the process when the needed data is already in memory.
When you start MySQL, by default the InnoDB Buffer Pool is cold and the warm up process can even take days sometimes…
So, you can already deduce that restarting mysqld is a source of
having a cold Buffer Pool as it will start empty. Another reason
to have a non optimal Buffer Pool is to load it unnecessary
pages. This can happen during a logical dump or load. If you
regularly do a
mysqldump for example (don’t forget
that MySQL Shell dump & load is better if you do logical
dumps, but introduces also the …