From mboxrd@z Thu Jan  1 00:00:00 1970
From: Kent Overstreet <koverstreet-hpIqsD4AKlfQT0dZR+AlfA@public.gmane.org>
Subject: Re: Issues dropping vm fs caches with kernel 3.5.2 + bcache master
Date: Mon, 20 Aug 2012 13:29:21 -0700
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To: Javier Marcet <jmarcet-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>
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On Mon, Aug 20, 2012 at 09:03:08AM +0200, Javier Marcet wrote:
> Hi,
> 
> I've recently set up a software RAID5 + bcache.
> 
> I'm using kernel 3.5.2 merged with bcache master branch. I'm quite
> happy with the performance but
> there is an important issue. I can't drop caches. Writing any number
> to /proc/sys/vm/drop_caches
> makes the system hungs.
> 
> Furthermore, so far I've been unable to curb bcache's memory
> consumption using the available
> sysctl knobs.
> 
> Is this problem known?

No I didn't know about that - thanks, I'll look into it.

Just out of curiousity, what are you doing? drop_caches isn't something
you want to use in normal operation...