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Fabrizio Magni wrote:
> Hi Frank,
> don't blame me if I throw this link as well.
> It is incomplete... but still I hope for a feedback.
>
> http://www.gesinet.it/oracle/blocksize.html
>
Feedback positive here. The only restriction I'm aware of as still valid is having a linux file system block size *larger* than the database block size.
Smaller (as in the submultiple you mention) is not such a problem nowadays. Used to, before the 2.4 kernel io elevators - or more precisely, the 2.3 kernel: first time the elevator code showed up.
But since then: yes there is a difference but not enough to warrant losing sleep over. Or at the very least I have yet to hit a combination where it becomes a true problem.
Having said that: don't go around slapping 1K fs block size on 16K db block sizes: the io elevator code is far from perfect and it's only in 2.4 kernel that the cfq more or less avoids such problems.
Note that the above is SPECIFIC to Linux. I have had a few problems in the past with some flavours of Unix and specific file systems other than ext3. My guess is those articles were at some stage extrapolations of information gathered from Unix, then tested in 2.1 kernel.
Since 2.4 kernel (RHAS3, Suse8?), not as much of an issue. Received on Mon Feb 13 2006 - 06:23:35 CST