From user-return-12718-apmail-couchdb-user-archive=couchdb.apache.org@couchdb.apache.org Fri Sep 17 01:22:47 2010 Return-Path: Delivered-To: apmail-couchdb-user-archive@www.apache.org Received: (qmail 31498 invoked from network); 17 Sep 2010 01:22:46 -0000 Received: from unknown (HELO mail.apache.org) (140.211.11.3) by 140.211.11.9 with SMTP; 17 Sep 2010 01:22:46 -0000 Received: (qmail 6232 invoked by uid 500); 17 Sep 2010 01:22:45 -0000 Delivered-To: apmail-couchdb-user-archive@couchdb.apache.org Received: (qmail 6176 invoked by uid 500); 17 Sep 2010 01:22:44 -0000 Mailing-List: contact user-help@couchdb.apache.org; run by ezmlm Precedence: bulk List-Help: List-Unsubscribe: List-Post: List-Id: Reply-To: user@couchdb.apache.org Delivered-To: mailing list user@couchdb.apache.org Received: (qmail 6168 invoked by uid 99); 17 Sep 2010 01:22:44 -0000 Received: from athena.apache.org (HELO athena.apache.org) (140.211.11.136) by apache.org (qpsmtpd/0.29) with ESMTP; Fri, 17 Sep 2010 01:22:44 +0000 X-ASF-Spam-Status: No, hits=2.2 required=10.0 tests=FREEMAIL_FROM,HTML_MESSAGE,RCVD_IN_DNSWL_NONE,SPF_PASS,T_TO_NO_BRKTS_FREEMAIL X-Spam-Check-By: apache.org Received-SPF: pass (athena.apache.org: domain of tjgillies@gmail.com designates 209.85.160.180 as permitted sender) Received: from [209.85.160.180] (HELO mail-gy0-f180.google.com) (209.85.160.180) by apache.org (qpsmtpd/0.29) with ESMTP; Fri, 17 Sep 2010 01:22:39 +0000 Received: by gyg13 with SMTP id 13so996653gyg.11 for ; Thu, 16 Sep 2010 18:22:18 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=gamma; h=domainkey-signature:mime-version:received:sender:received :in-reply-to:references:date:x-google-sender-auth:message-id:subject :from:to:content-type; bh=07is4UDes6flDp+3qqS+Ely9Qr8ZBAJ051rJRysdrz0=; b=lsydGw5owKRKEMfFFehODNV3kUYIGj5rFkDpD2nTgzmB5bVNTYs3uvfsbqtM5BLvWL 0ArilTNi3MTOvbbGiG95q8dEj2JAbrzVb3OkXVJwDvmHetb6p7qWvKn7Yen4v8I2rNhs V1pw1eRnEXMaRNZ5htKK70rVYfM5TkeJ9ITjQ= DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=mime-version:sender:in-reply-to:references:date :x-google-sender-auth:message-id:subject:from:to:content-type; b=vqT8OzU8k+scEIQhmpEnZwcxvRGLHq44Gil/x6yLjvtYineKj1NSx9iT9ZDzCVIXL5 1f4h25EIjoWkLOcZlSfnTIu4RJX/zO7KtUDISGem1htJBUlUAvJs/BKSusapt0qagYrW zxpYozN3Baa7/agL7jQLbIu9HN7aijNJ/48lc= MIME-Version: 1.0 Received: by 10.90.103.13 with SMTP id a13mr2725942agc.117.1284686538315; Thu, 16 Sep 2010 18:22:18 -0700 (PDT) Sender: tjgillies@gmail.com Received: by 10.90.235.8 with HTTP; Thu, 16 Sep 2010 18:22:18 -0700 (PDT) In-Reply-To: References: Date: Thu, 16 Sep 2010 18:22:18 -0700 X-Google-Sender-Auth: XsiYdNgjjJUQi9dI6DPnqKpP_hc Message-ID: Subject: Re: Which filesystem is best for deploying couchdb and why? From: Tyler Gillies To: user@couchdb.apache.org Content-Type: multipart/alternative; boundary=0016364ede86c3b73304906a64d2 --0016364ede86c3b73304906a64d2 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: quoted-printable Wow, thanks for the thought out writeup! On Thu, Sep 16, 2010 at 12:47 PM, Randall Leeds wr= ote: > Disclaimer: I'm no file systems expert. > > I recommend something with extents otherwise you might take a big > performance hit while couch deletes old db files after compaction. > Compression sounds cool as long as you can do it really fast (are > there setups where this happens in hardware?). > > reiserfs: > According to wikipedia it "still uses the big kernel lock (BKL) =E2=80=94= a > global kernel-wide lock" which makes performance on multiple cores > suffer. > It's big benefit, as I always understood it, is being able to pack > smile files together into single blocks. You will likely not have lots > of small files with Couch :-P > > xfs: > Delayed allocation might be a big performance win with a Couch. Since > outstanding writes are committed together in chunks and then fsync'd > all together I bet this feature would do good things for Couch > performance. > > ext(3|4) > I'd recommend ext4 over ext3. Delayed allocation like xfs as well as > the multiblock allocator should make it much better than ext3. You > also get extents. > > btrfs/zfs: > Some of the features of each sound interesting, but nothing that > stands out to me as "great for CouchDB". Snapshots and backups are > cool, but Couch is doing this for you already in a sense due to the > way the btree is appended: CouchDB documents are, in a sense, > copy-on-write. Checksumming is cool if you think it's important for > your data integrity. If you want snapshots for backup you can always > use CouchDB replication. > > If you run any tests I'd be very, very interested in seeing your results. > > -Randall > > On Thu, Sep 16, 2010 at 03:11, Metin Akat wrote: > > I'm sure almost everybody out there is using ext4/3 (including me), > > but what about filesystems like btrfs, zfs, reiserfs, xfs. Some of > > them have very appealing feature-sets (like compression for example, > > and we all know how greedy is couchdb for disk space). > > And I know that for example btrfs is not yet "recommended for > > production". But its time is coming. From what I see, Ubuntu 10.10 > > works flawlessly on btrfs. > > So I'd be happy if we have some discussion on the topic, instead of > > "everybody uses ext4, just use it" kind of stuff :). > > Couchdb was "alpha software" for years, and we all used it in > > production, so we are not afraid of alpha/beta software, as long as > > it's good :) > --=20 http://www.readwriteweb.com/about#tyler Ask me anything ! --0016364ede86c3b73304906a64d2--