From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 00B28C433EF for ; Thu, 21 Oct 2021 11:29:39 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id D29AC60F02 for ; Thu, 21 Oct 2021 11:29:38 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230463AbhJULbx (ORCPT ); Thu, 21 Oct 2021 07:31:53 -0400 Received: from mail.kernel.org ([198.145.29.99]:43460 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230374AbhJULbw (ORCPT ); Thu, 21 Oct 2021 07:31:52 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id C2E8960EFE; Thu, 21 Oct 2021 11:29:35 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1634815776; bh=mcc72ZcqDdMDWiL2WxtN09zO3LW9PCTKiI0ho3RGf3k=; h=Date:Subject:To:Cc:References:From:In-Reply-To:From; b=AIGa8F4hEJ9tysD3zEuLrV/8EzNpzbOIYGrO0kBy4fh+xFqC4Pxeg8KwwwPkTyGFG /SiGt8Rlaw5iZsW9mNKPUeHchALKfHAVmss2slYOu1KAqMe6FxpA/33Im/4+nuee6D 8EqYO+OmQUjMh7HCdZIJlNwqti6cc/WiC8eDgUuY+IlW8aqG4yT56LAfPeAi8O2QBc ajy60KmOnmJg43C0hj1ZhjK7KhTTgdRkUVuDjQt6e3+/wb6NgSqjCOjkMbeKCq8AKG rnj0YTE6R1EVI6dR0x9Mwib6f+ll4L6r61B4amIKRc5/RY8pdxg/j5+XYAcsdaQvyb vyaUVlm4J4Rng== Message-ID: <0e77ea3e-196e-cc41-91eb-abc89ca6d522@kernel.org> Date: Thu, 21 Oct 2021 19:29:33 +0800 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:91.0) Gecko/20100101 Thunderbird/91.2.0 Subject: Re: [f2fs-dev] [PATCH v5] f2fs: introduce fragment allocation mode mount option Content-Language: en-US To: Daeho Jeong , linux-kernel@vger.kernel.org, linux-f2fs-devel@lists.sourceforge.net, kernel-team@android.com Cc: Daeho Jeong References: <20210929181203.1606675-1-daeho43@gmail.com> From: Chao Yu In-Reply-To: <20210929181203.1606675-1-daeho43@gmail.com> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 2021/9/30 2:12, Daeho Jeong wrote: > From: Daeho Jeong > > Added two options into "mode=" mount option to make it possible for > developers to simulate filesystem fragmentation/after-GC situation > itself. The developers use these modes to understand filesystem > fragmentation/after-GC condition well, and eventually get some > insights to handle them better. > > "fragment:segment": f2fs allocates a new segment in ramdom position. > With this, we can simulate the after-GC condition. > "fragment:block" : We can scatter block allocation with > "max_fragment_chunk" and "max_fragment_hole" sysfs > nodes. f2fs will allocate 1.. > blocks in a chunk and make a hole in the length of > 1.. by turns in a newly allocated > free segment. Plus, this mode implicitly enables > "fragment:segment" option for more randomness. > > Signed-off-by: Daeho Jeong Reviewed-by: Chao Yu Thanks,