From mboxrd@z Thu Jan 1 00:00:00 1970 From: Joe Thornber Subject: Re: [PATCHES] convert dm-thin to use dm-bufio Date: Wed, 17 Aug 2011 09:26:57 +0100 Message-ID: <20110817082656.GA3267@ubuntu> References: <20110815090416.GE3159@ubuntu> <20110816091600.GA4284@ubuntu> Reply-To: device-mapper development Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: Content-Disposition: inline In-Reply-To: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: dm-devel-bounces@redhat.com Errors-To: dm-devel-bounces@redhat.com To: Mikulas Patocka Cc: dm-devel@redhat.com, "Alasdair G. Kergon" List-Id: dm-devel.ids On Tue, Aug 16, 2011 at 06:03:00PM -0400, Mikulas Patocka wrote: > The working set is 2% of memory or 1/4 of vmalloc space (whichever is > smaller). This can be changed in > "/sys/module/dm_bufio/parameters/dm_bufio_cache_size". > > Buffers are freed when they are unused for 60 seconds (can be changed in > "/sys/module/dm_bufio/parameters/dm_bufio_max_age"). > > Total size is divided by the number of active clients using dm-bufio. So > that each client gets a fair share. > > Writeback is done on commit. When 3/4 of the cache size is used, > background writeback is started. This all sounds good; get the locking interface in and I'll switch to bufio straight away. - Joe