If heavy traffic is causing the sessions table to lock up, it's probably a MyISAM table. You could flip that table to the memory engine, would probably alleviate heavy traffic issues.
Sessions tables don't need to be saved to the disk, since sessions data is volatile (non-permanent). I poked around a bit on this particular error.
Sessions tables don't need to be saved to the disk, since sessions data is volatile (non-permanent). I poked around a bit on this particular error.