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From: Kent Overstreet <kmo-PEzghdH756F8UrSeD/g0lQ@public.gmane.org>
To: Stefan Priebe - Profihost AG
	<s.priebe-2Lf/h1ldwEHR5kwTpVNS9A@public.gmane.org>
Cc: "linux-bcache-u79uwXL29TY76Z2rM5mHXA@public.gmane.org"
	<linux-bcache-u79uwXL29TY76Z2rM5mHXA@public.gmane.org>
Subject: Re: speed up dirty data cleaning
Date: Thu, 7 Nov 2013 18:49:04 -0800	[thread overview]
Message-ID: <20131108024904.GL3842@kmo> (raw)
In-Reply-To: <527BAF4B.9080609-2Lf/h1ldwEHR5kwTpVNS9A@public.gmane.org>

On Thu, Nov 07, 2013 at 04:18:35PM +0100, Stefan Priebe - Profihost AG wrote:
> After some time it seems to start writing out all the data at a good
> disk speed.
> 
> But how does bcache determine when to write which kind of data out of
> bcache.

There's a PD controller that tries to keep the amount of dirty data at
writeback_percent percentage of your cache size. But, since the dirty data
account was _still_ broken, that would screw up that PD controller.

Workaround is to set writeback_percent to 0

  parent reply	other threads:[~2013-11-08  2:49 UTC|newest]

Thread overview: 4+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2013-11-07 13:09 speed up dirty data cleaning Stefan Priebe - Profihost AG
     [not found] ` <527B90EF.10404-2Lf/h1ldwEHR5kwTpVNS9A@public.gmane.org>
2013-11-07 15:18   ` Stefan Priebe - Profihost AG
     [not found]     ` <527BAF4B.9080609-2Lf/h1ldwEHR5kwTpVNS9A@public.gmane.org>
2013-11-08  2:49       ` Kent Overstreet [this message]
2013-11-08  7:19         ` Stefan Priebe - Profihost AG

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