From owner-freebsd-performance@FreeBSD.ORG Tue Mar 18 12:00:49 2014 Return-Path: Delivered-To: freebsd-performance@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:1900:2254:206a::19:1]) (using TLSv1 with cipher ADH-AES256-SHA (256/256 bits)) (No client certificate requested) by hub.freebsd.org (Postfix) with ESMTPS id B1C2261F for ; Tue, 18 Mar 2014 12:00:49 +0000 (UTC) Received: from smtp.infracaninophile.co.uk (smtp6.infracaninophile.co.uk [IPv6:2001:8b0:151:1:3cd3:cd67:fafa:3d78]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mx1.freebsd.org (Postfix) with ESMTPS id 5691E3D7 for ; Tue, 18 Mar 2014 12:00:49 +0000 (UTC) Received: from ox-dell39.ox.adestra.com (no-reverse-dns.metronet-uk.com [85.199.232.226] (may be forged)) (authenticated bits=0) by smtp.infracaninophile.co.uk (8.14.8/8.14.8) with ESMTP id s2IC0Yrr029050 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES128-SHA bits=128 verify=NO) for ; Tue, 18 Mar 2014 12:00:40 GMT (envelope-from matthew@freebsd.org) DKIM-Filter: OpenDKIM Filter v2.8.3 smtp.infracaninophile.co.uk s2IC0Yrr029050 Authentication-Results: smtp.infracaninophile.co.uk/s2IC0Yrr029050; dkim=none reason="no signature"; dkim-adsp=none X-Authentication-Warning: lucid-nonsense.infracaninophile.co.uk: Host no-reverse-dns.metronet-uk.com [85.199.232.226] (may be forged) claimed to be ox-dell39.ox.adestra.com Message-ID: <53283557.4070105@freebsd.org> Date: Tue, 18 Mar 2014 12:00:23 +0000 From: Matthew Seaman User-Agent: Mozilla/5.0 (X11; FreeBSD amd64; rv:24.0) Gecko/20100101 Thunderbird/24.3.0 MIME-Version: 1.0 To: freebsd-performance@freebsd.org Subject: Re: FreeBSD 10 and PostgreSQL 9.3 scalability issues References: <5327B9B7.3050103@gmail.com> In-Reply-To: <5327B9B7.3050103@gmail.com> X-Enigmail-Version: 1.6 Content-Type: multipart/signed; micalg=pgp-sha512; protocol="application/pgp-signature"; boundary="TrvE6DU40kixEQgjbS3vUXBPeNnSpjw8k" X-Virus-Scanned: clamav-milter 0.98.1 at lucid-nonsense.infracaninophile.co.uk X-Virus-Status: Clean X-Spam-Status: No, score=-1.0 required=5.0 tests=AWL,BAYES_00,RDNS_NONE, SPF_SOFTFAIL autolearn=no version=3.3.2 X-Spam-Checker-Version: SpamAssassin 3.3.2 (2011-06-06) on lucid-nonsense.infracaninophile.co.uk X-Mailman-Approved-At: Tue, 18 Mar 2014 12:05:47 +0000 X-BeenThere: freebsd-performance@freebsd.org X-Mailman-Version: 2.1.17 Precedence: list List-Id: Performance/tuning List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Tue, 18 Mar 2014 12:00:49 -0000 This is an OpenPGP/MIME signed message (RFC 4880 and 3156) --TrvE6DU40kixEQgjbS3vUXBPeNnSpjw8k Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: quoted-printable On 03/18/14 03:12, Petr Janda wrote: > ust want to share these pgbench results done by DragonFlyBSD, and would= > like some input on why these numbers look so bad and what can be done t= o > improve (ie. kernel tunables etc) the performance. >=20 > http://lists.dragonflybsd.org/pipermail/users/attachments/20140310/4250= b961/attachment-0001.pdf Using ZFS as the backing for a RDBMS without: * Separate (fast) L2ARC devices * Tuning the ZFS block size to match the postgres IO block size * Setting primarycache to metadata * Tuning the ARC max so ZFS doesn't eat all the RAM * probably other things I can remember off-hand. That's what is wrong. ZFS is known to work particularly badly at the sort of small random IOs that RDBMSes generate (mostly because of the copy-on-write thing) without special tuning and extra hardware for caches. ie. You can't construct a fair test of database performance against other OSes/filesystems if you restrict yourself to using exactly the same hardware. Basically, install the FreeBSD box on UFS2 and try again. Cheers, Matthew --TrvE6DU40kixEQgjbS3vUXBPeNnSpjw8k Content-Type: application/pgp-signature; name="signature.asc" Content-Description: OpenPGP digital signature Content-Disposition: attachment; filename="signature.asc" -----BEGIN PGP SIGNATURE----- Version: GnuPG v2.0.22 (FreeBSD) Comment: Using GnuPG with Thunderbird - http://www.enigmail.net/ iQJ8BAEBCgBmBQJTKDVgXxSAAAAAAC4AKGlzc3Vlci1mcHJAbm90YXRpb25zLm9w ZW5wZ3AuZmlmdGhob3JzZW1hbi5uZXQxOUYxNTRFQ0JGMTEyRTUwNTQ0RTNGMzAw MDUxM0YxMEUwQTlFNEU3AAoJEABRPxDgqeTnFjYP/RL9xQktUXOHKTQLGSoPrH7b mrprdljjuIa8LHKhh08zyiAwU3V+OIk2JDYX4rSAjLYryRNWMEkEjNi7DTctgJny r5yefOGParhOTP6p9hxaxm2qFUQpPBjSS1V/+Igrd8DEjmfI6Uy5VwJwYR1nfQBQ lLf4Kpa9EUMSZnoJk+4SusoweySjcUBq0BjoGt+1wXpjk4410V38gDEVvdT3APe+ QKkobicvSWkjyrVkZ+o1kskjbvSxFefgc5POYOaJeCKrfgVWvFGirwT7vn8nEZ7N EkALwBtofOIKGeXENUMfH5zCdXVEw/D1zoMEQL0n0SPEuq/1GG9nm+Kvqsf7Z0zp 02PWOGzhbBdHE5Vng/o627wMUd2YrsjFxRkYEiq89sxQTmBqNGDWU+LA+WIi3xGT PUHMPwp/6xEIpLnXf2kxZMwt4fwEPiCJxJSzgKK2lmgj/8eIKjWNWbyyFEIsZMQp Q4LRJ9zFDo5rBe+Mo2du4M2B+vyismUsxr34l7lNXPQ4WiPLY69EbiJA24oBC+zI QsZWEUKHChdlnETeVcCwAA3bMB3Q3UmCHczTGktz0JGfpAQ5j9FpVlxbFkV/P9++ OEi4MFpDNzCJAJY5rS7wr5deROZzcpeFBDvbGsv5nkXhAlzqbUeX8EsJO+4AiPBH 9lYFQGVdJA39ttfg7JK5 =fodm -----END PGP SIGNATURE----- --TrvE6DU40kixEQgjbS3vUXBPeNnSpjw8k--