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To: Konstantin Belousov <kostikbel@gmail.com>
From: Ian FREISLICH <ianf@cloudseed.co.za>
Subject: Re: Filesystem wedges caused by r251446
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Konstantin Belousov wrote:
> > So, then did r251446 actually start using this value or did other
> > values get significantly tuned up?  I recall now setting this nearly
> > a year ago when we did our ZFS tuning and it was a four fold increase
> > on the defaults.
> 
> r251446 optimized the wakeups by only doing wakeups when runningbufspace
> actually crossed the lorunningspace.  Before, wakeups were performed
> always on the runningbufspace changes.
> 
> For ZFS, these settings are completely irrelevant, ZFS does not use
> buffer cache.

A year is so long ago...  It might have been tuning for our postgres
servers.

It might be worth while putting in a sanity check that doesn't allow
hirunningspace to be set lower than lorunningspace.

Thanks for your patience.

Ian

-- 
Ian Freislich