2 ms·
You have a good point that the app should track the difference between I/O submission times and I/O completion times. Can't speak for MySQL, but Oracle nowadays
by tanelpoder 5y ago
You have a good point that the app should track the difference between I/O submission times and I/O completion times. Can't speak for MySQL, but Oracle nowadays has two "wait events" for the DB Writer flow (that syncs dirty buffers from its buffer cache to disk):
1. db file async I/O submit
2. db file parallel write
(the 2nd one has such a name for historical reasons, but it's the I/O reaping/completion check timing, not the submission).