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=-0.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=no 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 4FEC2C2BA19 for ; Sun, 5 Apr 2020 09:50:05 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 298CA20675 for ; Sun, 5 Apr 2020 09:50:05 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726486AbgDEJuE (ORCPT ); Sun, 5 Apr 2020 05:50:04 -0400 Received: from ciao.gmane.io ([159.69.161.202]:41490 "EHLO ciao.gmane.io" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726455AbgDEJuE (ORCPT ); Sun, 5 Apr 2020 05:50:04 -0400 Received: from list by ciao.gmane.io with local (Exim 4.92) (envelope-from ) id 1jL1uj-000Xwd-UL for linux-btrfs@vger.kernel.org; Sun, 05 Apr 2020 11:50:01 +0200 X-Injected-Via-Gmane: http://gmane.org/ To: linux-btrfs@vger.kernel.org From: Achim Gratz Subject: Re: [RFC][PATCH v2] btrfs: ssd_metadata: storing metadata on SSD Date: Sun, 05 Apr 2020 10:22:00 +0200 Organization: Linux Private Site Message-ID: <87o8s6bavr.fsf@Rainer.invalid> References: <20200405071943.6902-1-kreijack@libero.it> Mime-Version: 1.0 Content-Type: text/plain User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/26.3 (gnu/linux) Cancel-Lock: sha1:SecahP3oVHNeYF4iZYzd3y+EJHE= Sender: linux-btrfs-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-btrfs@vger.kernel.org Goffredo Baroncelli writes: > This is an RFC; I wrote this patch because I find the idea interesting > even though it adds more complication to the chunk allocator. > > The core idea is to store the metadata on the ssd and to leave the data > on the rotational disks. BTRFS looks at the rotational flags to > understand the kind of disks. My comment really is only about his aspect of your proposal: I would consider a more general way of introducing a tiering of disks so that one can discern between slower and faster SSD as well. Regards, Achim. -- +<[Q+ Matrix-12 WAVE#46+305 Neuron microQkb Andromeda XTk Blofeld]>+ Factory and User Sound Singles for Waldorf rackAttack: http://Synth.Stromeko.net/Downloads.html#WaldorfSounds