Re: [PATCHES] O_DIRECT for WAL writes

On Wed, Jun 22, 2005 at 03:50:04PM -0400, Tom Lane wrote:
> The reason I question "automatic" is that you really want to test each
> drive being used, if the system has more than one; but Postgres has no
> idea what the actual hardware layout is, and so no good way to know what
> needs to be tested.

Would testing in the WAL directory be sufficient? Or at least better
than nothing? Of course we could test in the database directories as
well, but you never know if stuff's been symlinked elsewhere... err, we
can test for that, no?

In any case, it seems like it'd be good to try to test and throw a
warning if the drive appears to be caching or if we think the test might
not cover everything (ie symlinks in the data directory).
-- 
Jim C. Nasby, Database Consultant               decibel@decibel.org 
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