From owner-freebsd-hackers@FreeBSD.ORG  Thu Feb 22 17:37:02 2007
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Date: Thu, 22 Feb 2007 12:37:00 -0500
From: "Zaphod Beeblebrox" <zbeeble@gmail.com>
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Subject: Re: Fwd: Abyssmal dump cache efficiency
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On 2/21/07, Oliver Fromme <olli@lurza.secnetix.de> wrote:
>
> Peter Jeremy wrote:
> > I've found that you do get a worthwhile improvement in dump|restore
> > performance by introducing a large (10's of MB) fifo between them.
> > This helps reduce synchronisation between dump and restore (so that
> > dump can continue to read whilst restore is busy writing a batch of
> > small files and vice versa).  There's a suitable port but I can't
> > recall the name because I wrote my own.
>
> There are several.  The most popular ones are probably
> misc/team and misc/buffer.


I can certainly vouch for that , too.  I generally use "team 1m 32" (total
of 32meg of buffer).  Team seems to not want to buffer more than 1m per
process and I think 32 is the max # of processes.