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 X-Spam-Level: X-Spam-Status: No, score=-5.3 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE, SPF_PASS,USER_AGENT_SANE_1 autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 936C4C5DF60 for ; Fri, 8 Nov 2019 19:44:32 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 63471206DF for ; Fri, 8 Nov 2019 19:44:32 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=toxicpanda-com.20150623.gappssmtp.com header.i=@toxicpanda-com.20150623.gappssmtp.com header.b="HEOcbVkJ" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1731286AbfKHTob (ORCPT ); Fri, 8 Nov 2019 14:44:31 -0500 Received: from mail-qv1-f68.google.com ([209.85.219.68]:37888 "EHLO mail-qv1-f68.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729895AbfKHTob (ORCPT ); Fri, 8 Nov 2019 14:44:31 -0500 Received: by mail-qv1-f68.google.com with SMTP id q19so2680915qvs.5 for ; Fri, 08 Nov 2019 11:44:30 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=toxicpanda-com.20150623.gappssmtp.com; s=20150623; h=date:from:to:cc:subject:message-id:references:mime-version :content-disposition:in-reply-to:user-agent; bh=neVziem/uOoLRPCjfa3hSFj2VvZXyM97Kr1be1BRmQY=; b=HEOcbVkJckQb2IyLJdDhJYvZqORIDL1qY+Nk57uXv8+hnjQbxx/hsNzNUUdOPJ9EOk Li6ztI7fGJUTtwmb/Pyxg62mCx7tT9zWUjzxAPV+98c7RaBF/kSVT/3d2LKf1VyYG3aG VJfy1q9fYzPobnyY13AnPK7dUkewEBnN+j/5sQjaQJYbMEjQKV7/LOdDEEhkRYGBQKna lkwBw8UNF/OEVBQ5lYz2NUN5ftOVQ7zoE8MRkvvt7H/eHYQI4N+vHUbvgHeHppIp1tdQ 61WCcKWVLfdH2ucJig6maDHfNNsevpkvnwaaTU43Q3jTn/MConOR/8UDhSJ3BBn83fhE NO6A== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:from:to:cc:subject:message-id:references :mime-version:content-disposition:in-reply-to:user-agent; bh=neVziem/uOoLRPCjfa3hSFj2VvZXyM97Kr1be1BRmQY=; b=qVftgY4HAJb8BRGfVEz1xTGjehav3tfE/PWJshWwHY0VNMWdq2dVVZNPbiTzM9NAf9 9B++Uqi7ke+rw1PCnplIAHbInAI24+qn5SBbCS8uoW5NuGkT8LGWyW0TgvlL+xzar8SI opktoTkByqPRAAy808bZrC1emrrBFkJBKLowBp8510lGMb3E6pU0RtQzUN3z0Ot+XmNq 4XjtSTpvrYlJ/PYbVyObLVukRuPhPp44ertNrgITj2+XnaE6r0SGj95I+jl8sX+Xx4Ow EAqkF8boAZfXZ4ikEOQvzNngEYRMXgNoGpIyjNbRWZa92Ytbz1gFSoBtrQPNNoNTsOu9 6tmw== X-Gm-Message-State: APjAAAUtuQV7W7vyInWWuMpM7CCd/Ta/ExfhNozXF6ghFaFZozRYTPjN AEO71WzC024cQOyxVjzW1cxT/g== X-Google-Smtp-Source: APXvYqwNHDGsLfzAID8cBRkMvvW38egTau/xu2Kce0Y0zdsOfH59QAszqFdgbxkQMcqksXeO3DH3pw== X-Received: by 2002:ad4:4e2c:: with SMTP id dm12mr11363263qvb.195.1573242270438; Fri, 08 Nov 2019 11:44:30 -0800 (PST) Received: from localhost ([2620:10d:c091:480::1852]) by smtp.gmail.com with ESMTPSA id y24sm3181935qki.104.2019.11.08.11.44.29 (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Fri, 08 Nov 2019 11:44:30 -0800 (PST) Date: Fri, 8 Nov 2019 14:44:28 -0500 From: Josef Bacik To: Dennis Zhou Cc: David Sterba , Chris Mason , Josef Bacik , Omar Sandoval , kernel-team@fb.com, linux-btrfs@vger.kernel.org Subject: Re: [PATCH 17/22] btrfs: have multiple discard lists Message-ID: <20191108194428.il2fs4khcvg72uti@macbook-pro-91.dhcp.thefacebook.com> References: <9affe695998972620340031ccc95caac909bfe4b.1571865774.git.dennis@kernel.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <9affe695998972620340031ccc95caac909bfe4b.1571865774.git.dennis@kernel.org> User-Agent: NeoMutt/20180716 Sender: linux-btrfs-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-btrfs@vger.kernel.org Archived-At: List-Archive: List-Post: On Wed, Oct 23, 2019 at 06:53:11PM -0400, Dennis Zhou wrote: > Non-block group destruction discarding currently only had a single list > with no minimum discard length. This can lead to caravaning more > meaningful discards behind a heavily fragmented block group. > > This adds support for multiple lists with minimum discard lengths to > prevent the caravan effect. We promote block groups back up when we > exceed the BTRFS_ASYNC_DISCARD_MAX_FILTER size, currently we support > only 2 lists with filters of 1MB and 32KB respectively. > > Signed-off-by: Dennis Zhou Reviewed-by: Josef Bacik Thanks, Josef