From owner-freebsd-performance@FreeBSD.ORG Wed Nov 24 01:40:07 2010 Return-Path: Delivered-To: freebsd-performance@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id 376E71065672 for ; Wed, 24 Nov 2010 01:40:07 +0000 (UTC) (envelope-from gofp-freebsd-performance@m.gmane.org) Received: from lo.gmane.org (lo.gmane.org [80.91.229.12]) by mx1.freebsd.org (Postfix) with ESMTP id D773B8FC17 for ; Wed, 24 Nov 2010 01:40:06 +0000 (UTC) Received: from list by lo.gmane.org with local (Exim 4.69) (envelope-from ) id 1PL4L6-00021T-N3 for freebsd-performance@freebsd.org; Wed, 24 Nov 2010 02:40:04 +0100 Received: from bl13-84-33.dsl.telepac.pt ([85.246.84.33]) by main.gmane.org with esmtp (Gmexim 0.1 (Debian)) id 1AlnuQ-0007hv-00 for ; Wed, 24 Nov 2010 02:40:04 +0100 Received: from luis.neves by bl13-84-33.dsl.telepac.pt with local (Gmexim 0.1 (Debian)) id 1AlnuQ-0007hv-00 for ; Wed, 24 Nov 2010 02:40:04 +0100 X-Injected-Via-Gmane: http://gmane.org/ To: freebsd-performance@freebsd.org From: Luis Neves Date: Wed, 24 Nov 2010 01:30:01 +0000 Lines: 23 Message-ID: References: Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit X-Complaints-To: usenet@dough.gmane.org X-Gmane-NNTP-Posting-Host: bl13-84-33.dsl.telepac.pt User-Agent: Mozilla/5.0 (X11; U; Linux x86_64; en-US; rv:1.9.2.12) Gecko/20101027 Thunderbird/3.1.6 In-Reply-To: X-Mailman-Approved-At: Wed, 24 Nov 2010 02:57:13 +0000 Cc: freebsd-hackers@freebsd.org Subject: Re: PostgreSQL performance scaling X-BeenThere: freebsd-performance@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Performance/tuning List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Wed, 24 Nov 2010 01:40:07 -0000 On 11/22/2010 12:21 AM, Ivan Voras wrote: > The "semwait" part is from PostgreSQL - probably shared buffer locking, > but there's a large number of processes regularly in sbwait - maybe > something can be optimized here? I think this paper was mentioned before, did you read it?... "An Analysis of Linux Scalability to Many Cores"? ABSTRACT. "This paper analyzes the scalability of seven system applications (Exim, memcached, Apache, PostgreSQL, gmake, Psearchy, and MapReduce) running on Linux on a 48- core computer." The paper is about Linux, but it also focus on some changes that can be made to PostgreSQL to achieve better concurrency. -- Luis Neves