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Date: Sun, 4 May 2008 16:08:02 +0200
From: Gary Jennejohn <gary.jennejohn@freenet.de>
To: "Daniel Andersson" <engywook@gmail.com>
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Cc: freebsd-fs@freebsd.org
Subject: Re: Choppy performance.
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On Sun, 4 May 2008 11:03:30 +0200
"Daniel Andersson" <engywook@gmail.com> wrote:

> > vm.kmem_size_max="1073741824"
> >  vm.kmem_size="1073741824"
> >  KVA_PAGES=512
> >  Write speed in 8 disks (raidz) is 40 Mb/sec and very choppy.
> >  If I change to vm.kmem_size_max="999M", write speed increase in 4 times
> >  (160Mb/sec). I think this is bug.
> >  What is yours configuration?
> >
> My loader.conf(AMD64):
> 
> vfs.zfs.prefetch_disable=1
> vm.kmem_size_max="1073741824"
> vm.kmem_size="1073741824"
> 
> I'll try setting it to 999M instead, thanks!
> 

I just tried setting it to 999M for kicks (amd64) and saw no significant
speed up doing a ``make -j4 buildworld''.  I only saw a time difference
of 20 seconds between 1024M and 999M, which is just in the noise.

---
Gary Jennejohn