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From: Tom Samplonius <tom@sdf.com>
To: Sean Chittenden <sean@chittenden.org>
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cc: Jason Stone <freebsd-performance@dfmm.org>
Subject: Re: Tuning for PostGreSQL Database
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On Mon, 21 Jul 2003, Sean Chittenden wrote:

> > > Softupdates on, async off.  Softupdates is just a better async.
> > 
> > postgresql fsync's all its files before returning from a commit in
> > order to ensure durability, right?  Does softupdates interfere with
> > the functioning of sync(2)/fsync(2)?
> 
> It can, yes, but that's the risk of soft updates.  From tuning(7):

  No it can't.  Regardless of how softupdates re-orders filesystem
activity, fsync flushes all dirty buffers.


Tom