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Hoe can I reduce my Avergae Disk Queue length when using MySQL


I have found th eproblem of my slow server. It seems my Average Disk Queue Length peaks at 37! Apparently it should be no more than 2!
All that is on that disk is the MySql datafile.
What I have done is made a copt of a 500MB MyIsam table and converted it to Innodb, which is now about 1 Gig.
When I run my site against the innodb table, I get very high Disk I/O to the datafile.
I have plenty of physical memory left and the cpu is not overloaded, its just the disk access thats killing my server.
I have tried changing all the parameters but cant seem to get the disk accees down.
Any Ideas what I should be changing?

Im only running less than 100 connections.
1 Solution
Lost any indexes while converting or they need maintenance?  Sorry but can't help you technicaly for MySql
How many harddrives do you have? If the perfmon reports 37 and you have 10 hard drives in your diskarray then your diskqueue lenght is only 3,7 ( 37 divided by number of harddrives )

-Make sure you are not doing any table scans
-Make sure you are only returning as much data you need
-Make sure you are using as narrow columns as you can
-Make sure you have correct indexes
-Make sure your indexes are not fragmented
-Make sure your indexes have high selectivity ( less then 10% )


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