25 jun 2008 kl. 17.45 skrev Greg Smith:
On Wed, 25 Jun 2008, Henrik wrote:
Would you turn off fsync if you had a controller with BBU? =)
Turning off fsync has some potential to introduce problems even in
that environment, so better not to do that. The issue is that you
might have, say, 1GB of OS-level cache but 256MB of BBU cache, and
if you turn fsync off it won't force the OS cache out to the
controller when it's supposed to and that can cause corruption.
Also, if you've got a controller with BBU, the overhead of fsync for
regular writes is low enough that you don't really need to turn it
off. If writes are cached the fsync is almost free.
Thanks for a thoroughly answer. I guess I wont be turning of fsync. :)
Thanks Greg!
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* Greg Smith [EMAIL PROTECTED] http://www.gregsmith.com
Baltimore, MD
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