From: Theodore Ts'o Subject: Re: Please help: Is ext4 counting trims as writes, or is something killing my SSD? Date: Thu, 12 Sep 2013 11:28:45 -0400 Message-ID: <20130912152845.GG12918@thunk.org> References: <20130912141856.GA17640@jak-x230> <1378997643.28638.53.camel@hp-a6734f> <20130912151955.GA19285@jak-x230> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii To: Julian Andres Klode , Calvin Walton , linux-ext4@vger.kernel.org Return-path: Received: from imap.thunk.org ([74.207.234.97]:59030 "EHLO imap.thunk.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752017Ab3ILP2t (ORCPT ); Thu, 12 Sep 2013 11:28:49 -0400 Content-Disposition: inline In-Reply-To: <20130912151955.GA19285@jak-x230> Sender: linux-ext4-owner@vger.kernel.org List-ID: Ext4 is getting this information from the block layer. Specifically, it's calling part_stat_read(bd_part, sectors[WRITE]) to get the statistics information it uses to caluclate how many kb have been written. I'm not a block layer expert, but it may very well be the case that TRIMS are being counted as requests. Requests are categorized as either READS or WRITES, and I don't see any special casing for non r/w requests in block/blk-core.c. Regards, - Ted