[CentOS] disk I/O problems and Solutions

[Blake Hudson]

I would second what another poster stated, to look at DB/RAM 
optimizations. If possible, you should have enough RAM in the system to 
hold your entire DB in memory - and your db software should be setup to 
take advantage of that memory.

Since you stated that your system is only having trouble at writes, 
doing batch inserts, I would look at how you are doing these batch 
inserts and see if you can optimize this by using techniques to delay 
key writes or adjust locking mechanisms on the insert. Some databases 
have special insert from file or bulk insert operations that are much 
faster than running many single row inserts - be sure you are taking 
advantage of these methods.

--Blake