From owner-freebsd-current@FreeBSD.ORG Sat Jun 28 10:14:33 2014 Return-Path: Delivered-To: freebsd-current@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [8.8.178.115]) (using TLSv1 with cipher ADH-AES256-SHA (256/256 bits)) (No client certificate requested) by hub.freebsd.org (Postfix) with ESMTPS id AB804102; Sat, 28 Jun 2014 10:14:33 +0000 (UTC) Received: from melon.pingpong.net (melon.pingpong.net [79.136.116.200]) by mx1.freebsd.org (Postfix) with ESMTP id 6BCE22915; Sat, 28 Jun 2014 10:14:33 +0000 (UTC) Received: from [10.0.1.16] (h-43-145.a357.priv.bahnhof.se [79.136.43.145]) by melon.pingpong.net (Postfix) with ESMTPA id D11A037FFC; Sat, 28 Jun 2014 12:08:39 +0200 (CEST) References: <20140627125613.GT93733@kib.kiev.ua> <201406271057.53599.jhb@freebsd.org> <20140627163407.GX93733@kib.kiev.ua> In-Reply-To: <20140627163407.GX93733@kib.kiev.ua> Mime-Version: 1.0 (1.0) Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset=us-ascii Message-Id: <35090A62-2DB8-493C-A5ED-ADB1BC193640@pingpong.net> X-Mailer: iPad Mail (9B206) From: Palle Girgensohn Subject: Re: PostgreSQL performance on FreeBSD Date: Sat, 28 Jun 2014 12:08:39 +0200 To: Konstantin Belousov Cc: "freebsd-current@freebsd.org" , "performance@freebsd.org" X-BeenThere: freebsd-current@freebsd.org X-Mailman-Version: 2.1.18 Precedence: list List-Id: Discussions about the use of FreeBSD-current List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Sat, 28 Jun 2014 10:14:33 -0000 27 jun 2014 kl. 18:34 skrev Konstantin Belousov : > On Fri, Jun 27, 2014 at 10:57:53AM -0400, John Baldwin wrote: >> On Friday, June 27, 2014 8:56:13 am Konstantin Belousov wrote: >>> Hi, >>> I did some measurements and hacks to see about the performance and >>> scalability of PostgreSQL 9.3 on FreeBSD, sponsored by The FreeBSD >>> Foundation. >>>=20 >>> The results are described in https://kib.kiev.ua/kib/pgsql_perf.pdf. >>> The uncommitted patches, referenced in the article, are available as >>> https://kib.kiev.ua/kib/pig1.patch.txt >>> https://kib.kiev.ua/kib/patch-2 >>=20 >> Did you run the same benchmark on the same hardware with any other OS's t= o=20 >> compare results? >=20 > No. >=20 > FWIW, before the failing after the 30 clients is corrected, I do not > think it is much interesting to do such comparision. This is great work! Does anybody know how far back in FreeBSD versions using posix semaphore ins= tead of sysv would make a difference? It seems we need a rather current ver= sion? 8.x did not support it at all, at some point at lest, and in 9 it was b= uggy. I could add he patch-2 to the port, but I reckon it needs a conditiona= l based on FreeBSD version? The clang bug should go upstreams, right? I have seen similar curves, presented by Greg Smith (PostgreSQL hacker) wher= e he concluded that there is no point in running more than 50 concurrent con= nections. This was for Linux. In your measures, the knee is at 30. That's sa= id, FreeBSD could and should do better, but probably there is a limit where t= here will be a knee in the graph and performance will drop. It should be mor= e than 30, though, as you rightly commented. Do you any ideas to pursue this further apart from complicated rewrites like= DragonFly? Palle=