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Go Back  dBforums > Database Server Software > DB2 > AIX AIO Servers for DB2 i/o improvement

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Old 08-11-06, 10:46
Perfman Perfman is offline
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AIX AIO Servers for DB2 i/o improvement

Hello, Has anyone used AIX servers to improve DB2 ? I have read conflicting material on this subject.
Thanks
George
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Old 08-11-06, 13:17
dbamota dbamota is offline
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Yes we have used it. recommended settings are
MaxServers The lower of 10 * number of disks or 10 times the number of processors in the machine.
MinServers MaxServers /2.

You could start with these values and by monitoring AIO usage, tweak those settings. You also have to properly configure numioservers, pagecleaners, and sync up your extent size, maxpgahead etc. Also use blocks in your bufferpools and proper filecache %.
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Old 08-11-06, 13:37
Perfman Perfman is offline
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I have used this in a large oracle environment(35 db's) p570/64gb real, shark,san tech and have seen the wait on I/O drop tremendously. Is this what you have observed on your DB2 server ? If not, what did you measure before and after to gauge improvement ?
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George
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Old 08-11-06, 16:50
cchattoraj cchattoraj is offline
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aioservers are not optional, i think since V8. db2 will not start without aioservers being available.

The recommendation from dbamota is similar to what we used to decide how many to make available. Keep in mind that aioservers start as needed.
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