11-12-2008
CIO/DIO and JFS2 read ahead
Hi Guys,
I wonder if after enabling CIO/DIO at the filesystem level and assuming that CIO/DIO will bypass the JFS2 read ahead available when not using CIO/DIO my questionis what parameters I can play with to tune/improve the CIO in order to obtain similar performance for sequential reads ( backups or big scans). I believe that while using file system caching/buffering read ahead plays a huge performance role. So any advise on how/what parameters I should consider modify in order to improve the CIO/DIO performance for large sequential reads.
Thanks in Advance.
Harby.
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