James Foris wrote:
Nathan Scott wrote:
Hi James,
On Mon, Sep 13, 2004 at 11:56:33AM -0500, James Foris wrote:
More correctly, it happened between 2.6.5 and 2.6.5-bk1
So..... something in the 2.6.5-bk1 patchset caused the change.
Any suggestions where to begin looking (other than fs/direct_io.x) ?
http://kernel.org/pub/linux/kernel/v2.6/snapshots/old/patch-2.6.5-bk1.log
Yup... a bunch more.
"Major surgery against the pagecache, radix-tree and writeback code"
The interesting question is; why do XFS and REISER suffer under O_DIRECT
when other file systems improve? And why does s/w RAID0 with an external
journal suffer much worse than a simple file system with an internal
journal?
Do these questions suggest anyplace else to look ?
Cache invalidation before and after O_DIRECT seems like a good starting
point. The raid0 external journal thing is probably a separate issue.
Steve
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