Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932762Ab0HDMyO (ORCPT ); Wed, 4 Aug 2010 08:54:14 -0400 Received: from ironport2-out.teksavvy.com ([206.248.154.183]:8560 "EHLO ironport2-out.pppoe.ca" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S932619Ab0HDMyN (ORCPT ); Wed, 4 Aug 2010 08:54:13 -0400 X-Greylist: delayed 579 seconds by postgrey-1.27 at vger.kernel.org; Wed, 04 Aug 2010 08:54:13 EDT X-IronPort-Anti-Spam-Filtered: true X-IronPort-Anti-Spam-Result: ApIBAD79WExLd/sX/2dsb2JhbAAHgw7PCZIIgSaDInME X-IronPort-AV: E=Sophos;i="4.55,315,1278302400"; d="scan'208";a="71618333" Message-ID: <4C5960B0.7020003@teksavvy.com> Date: Wed, 04 Aug 2010 08:44:32 -0400 From: Mark Lord User-Agent: Mozilla/5.0 (X11; U; Linux i686; en-US; rv:1.9.2.7) Gecko/20100713 Thunderbird/3.1.1 MIME-Version: 1.0 To: Nigel Cunningham CC: LKML , pm list Subject: Re: 2.6.35 Regression: Ages spent discarding blocks that weren't used! References: <4C58C528.4000606@tuxonice.net> In-Reply-To: <4C58C528.4000606@tuxonice.net> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 697 Lines: 16 Looks to me like more and more things are using the block discard functionality, and as predicted it is slowing things down enormously. The problem is that we still only discard tiny bits (a single range still??) per TRIM command, rather than batching larger ranges and larger numbers of ranges into single TRIM commands. That's a very poor implementation, especially when things start enabling it by default. Eg. the swap code, mke2fs, etc.. Ugh. -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/