Ross S. W. Walker wrote:
Ross S. W. Walker wrote:
Yes, IO starvation can occur under heavy load.
But it should stall the process needing to write, not everything.
There is only 1 disk though and if that disk is busy writing it can't read.
But if it weren't for the accumulation of stuff in the raid card queue, other processes should get an equal shot fairly quickly. I think that raid card just treats draining the whole queue as one operation.
You would also notice a dramatic speed increase in MySQL.
I'm not sure the needed temp table space is predictable. I've seen mysql be pretty dumb about how it does a select that joins several tables.
True, but take an average and that should suffice, MySQL will wait if temp space fills up.
What does that mean if it needs more than the available space to complete a single operation - like a multi-table join that decides to copy the whole tables to temp files?