From mboxrd@z Thu Jan  1 00:00:00 1970
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Date: Tue, 03 Sep 2013 12:54:40 +0200
From: Zdenek Kabelac <zkabelac@redhat.com>
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Subject: Re: [linux-lvm] howto speed-up thinpool-devices?
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To: LVM general discussion and development <linux-lvm@redhat.com>
Cc: Oliver Rath <rath@mglug.de>

Dne 24.8.2013 10:42, Oliver Rath napsal(a):
> Hi list,
>
> Im using thinpool-devices (and snapshots, too). I know, thinpool-devices
> arent the fastest one, but maybe there could make more use of read (and
> maybe write) caching. In my test-system are 32GB of ram, but there is a
> max use of cache about <1GB, not more, by heavily use of these devices.
>
> Is it possible to speed up the reading with growing up the cache use?
> The /sys/block/dm-X/.. directories have lots of parameters, but Im not
> experienced for that. Maybe Im looking at the wrong place and modifying
> kernel parameters (scheduler etc.) are the better way?
>


You  could look at lot of Howto text around various kernel settings i.e.:

http://en.wikipedia.org/wiki/Swappiness
https://www.kernel.org/doc/Documentation/sysctl/vm.txt

Check with Google for more hints.

Zdenek