From owner-freebsd-fs@freebsd.org Thu Nov 22 16:07:04 2018 Return-Path: Delivered-To: freebsd-fs@mailman.ysv.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2610:1c1:1:606c::19:1]) by mailman.ysv.freebsd.org (Postfix) with ESMTP id 854A6114B49D for ; Thu, 22 Nov 2018 16:07:04 +0000 (UTC) (envelope-from ben.rubson@gmail.com) Received: from mail-yw1-xc33.google.com (mail-yw1-xc33.google.com [IPv6:2607:f8b0:4864:20::c33]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (Client CN "smtp.gmail.com", Issuer "Google Internet Authority G3" (verified OK)) by mx1.freebsd.org (Postfix) with ESMTPS id D76107B77D for ; Thu, 22 Nov 2018 16:07:03 +0000 (UTC) (envelope-from ben.rubson@gmail.com) Received: by mail-yw1-xc33.google.com with SMTP id x2so3787918ywc.9 for ; Thu, 22 Nov 2018 08:07:03 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=from:content-transfer-encoding:mime-version:subject:message-id:date :to; bh=v/O1gjXAdCxfz0tnloImFqcP+yBEaPbW8+OeHftW+gg=; b=Y06GA/GnBPddMdWkoEf3Z5nKEwiaIAYY/G7Jtzx7w639PJzhCT912f0Rv3v8sclFnV Xd8MructJrryKeeYPx1D+KAQC/BfH6XuqsIwJnkxCeE+PDm35Hthqg7lYVH8FKFBBQJQ fs4VQgJr1F8TfSkdH/YX1XS+iPdH0M5RgtMaQKMgbVk2pI3npswYea3aQA5P5VOZgW/t EIifIHmCNGChZijwNAM23EBBkNT5ULodgqOKdgZMpVRc0aGaJO3p+9ROOMUH91JRxskv jo4xnFcGyQVtldUswT0jacZKp0MJorueCOu4t8gPqdY6TerU5bS5Gh42lWQHloYlg8/o dYrw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:content-transfer-encoding:mime-version :subject:message-id:date:to; bh=v/O1gjXAdCxfz0tnloImFqcP+yBEaPbW8+OeHftW+gg=; b=cn530TNrLN49sgvMLlEpDsZaG30a0csbji6TY6p7RBGBAUrefevlq9tsm3RD5IUBJX f9TTx1jJG/wJJ8m/OQTI579YWE9+YNtRhnr9iqz/nHESZT+7OQcljtjl1VBHZr4W4aOU 1hvCSCcNCQpQyGrWJ05IgLBvUuEJnbjNt2A0ekfbkfxNX/oF1SlnuxtuTzp3HHA7IJ9q 8xHaS+xDhYxdQp68yEb9f+AxJbjRzjZxLP9V6yTUL4EutZCzh7f2YVbOICU0DIrc2dm0 tWgKWcCYbSN+TgyIOqNy4vjg/XGIQtrgAYvOP3BAz7oQ0QktJg9HxMi5XRD/rKl5LGkL K9XQ== X-Gm-Message-State: AGRZ1gK6hHFVhMDnRLLIOQe0oTUgbixiDrhJVt/a2GvlYr0/A4Sckamo 2gfGNfR/jGhC4nFDGM8RM73nmIkm X-Google-Smtp-Source: AJdET5fDxvRhoYDieQL0LawostBhn1cMH2ATfKnpRpP1gI68lEMZYzjK6uj0Ln06s2pHWfafM8X/jg== X-Received: by 2002:a81:6c51:: with SMTP id h78mr11931368ywc.116.1542902823245; Thu, 22 Nov 2018 08:07:03 -0800 (PST) Received: from bens-mac.local (amontpellier-652-1-72-201.w109-210.abo.wanadoo.fr. [109.210.55.201]) by smtp.gmail.com with ESMTPSA id g70sm1625371ywe.105.2018.11.22.08.07.01 for (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Thu, 22 Nov 2018 08:07:02 -0800 (PST) From: Ben RUBSON Content-Type: text/plain; charset=us-ascii; delsp=yes; format=flowed Content-Transfer-Encoding: 7bit Mime-Version: 1.0 (Mac OS X Mail 11.5 \(3445.9.1\)) Subject: [ZFS] Metadata Allocation Classes Message-Id: <82E338C0-09E3-4648-B49B-C028A03B71D7@gmail.com> Date: Thu, 22 Nov 2018 17:06:59 +0100 To: freebsd-fs@freebsd.org X-Mailer: Apple Mail (2.3445.9.1) X-Rspamd-Queue-Id: D76107B77D X-Spamd-Result: default: False [-4.16 / 15.00]; RCVD_VIA_SMTP_AUTH(0.00)[]; FREEMAIL_FROM(0.00)[gmail.com]; R_SPF_ALLOW(-0.20)[+ip6:2607:f8b0:4000::/36]; MV_CASE(0.50)[]; TO_DN_NONE(0.00)[]; RCVD_COUNT_THREE(0.00)[3]; DKIM_TRACE(0.00)[gmail.com:+]; DMARC_POLICY_ALLOW(-0.50)[gmail.com,none]; MX_GOOD(-0.01)[cached: alt3.gmail-smtp-in.l.google.com]; NEURAL_HAM_SHORT(-0.91)[-0.910,0]; FROM_EQ_ENVFROM(0.00)[]; IP_SCORE(-0.74)[ipnet: 2607:f8b0::/32(-2.10), asn: 15169(-1.51), country: US(-0.09)]; RCVD_TLS_LAST(0.00)[]; FREEMAIL_ENVFROM(0.00)[gmail.com]; ASN(0.00)[asn:15169, ipnet:2607:f8b0::/32, country:US]; TAGGED_FROM(0.00)[]; ARC_NA(0.00)[]; NEURAL_HAM_MEDIUM(-1.00)[-1.000,0]; R_DKIM_ALLOW(-0.20)[gmail.com]; MID_RHS_MATCH_FROM(0.00)[]; FROM_HAS_DN(0.00)[]; TO_MATCH_ENVRCPT_ALL(0.00)[]; NEURAL_HAM_LONG(-1.00)[-1.000,0]; MIME_GOOD(-0.10)[text/plain]; PREVIOUSLY_DELIVERED(0.00)[freebsd-fs@freebsd.org]; RCPT_COUNT_ONE(0.00)[1]; RCVD_IN_DNSWL_NONE(0.00)[3.3.c.0.0.0.0.0.0.0.0.0.0.0.0.0.0.2.0.0.4.6.8.4.0.b.8.f.7.0.6.2.list.dnswl.org : 127.0.5.0] X-Rspamd-Server: mx1.freebsd.org X-BeenThere: freebsd-fs@freebsd.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Filesystems List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Thu, 22 Nov 2018 16:07:04 -0000 Hi, Intel has pushed the "Metadata Allocation Classes" feature to ZFS on Linux. This allows to store metadata on a so called "special" VDEV, made of SSD for instance. This looks really promising. I wrote a patch 2 years ago which pins metadata in L2ARC, at eviction time. This really helps with some specific workloads. But "Metadata Allocation Classes" should be one step further in terms of performance. Simple question, do you plan to backport this feature to FreeBSD ? Or do you first wait for it to reach Illumos (does not seem to be there yet) ? ZoL discussion : https://github.com/zfsonlinux/zfs/issues/3779 ZoL PR : https://github.com/zfsonlinux/zfs/pull/5182 Thank you very much ! Ben