From owner-freebsd-performance@freebsd.org Wed Jun 22 10:02:54 2016 Return-Path: Delivered-To: freebsd-performance@mailman.ysv.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:1900:2254:206a::19:1]) by mailman.ysv.freebsd.org (Postfix) with ESMTP id 6E24AB3B0F1 for ; Wed, 22 Jun 2016 10:02:54 +0000 (UTC) (envelope-from kostikbel@gmail.com) Received: from mailman.ysv.freebsd.org (mailman.ysv.freebsd.org [IPv6:2001:1900:2254:206a::50:5]) by mx1.freebsd.org (Postfix) with ESMTP id 4E7C324F4 for ; Wed, 22 Jun 2016 10:02:54 +0000 (UTC) (envelope-from kostikbel@gmail.com) Received: by mailman.ysv.freebsd.org (Postfix) id 48B9BB3B0EE; Wed, 22 Jun 2016 10:02:54 +0000 (UTC) Delivered-To: performance@mailman.ysv.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:1900:2254:206a::19:1]) by mailman.ysv.freebsd.org (Postfix) with ESMTP id 435E9B3B0EB; Wed, 22 Jun 2016 10:02:54 +0000 (UTC) (envelope-from kostikbel@gmail.com) Received: from kib.kiev.ua (kib.kiev.ua [IPv6:2001:470:d5e7:1::1]) (using TLSv1 with cipher DHE-RSA-CAMELLIA256-SHA (256/256 bits)) (Client did not present a certificate) by mx1.freebsd.org (Postfix) with ESMTPS id AA01324EE; Wed, 22 Jun 2016 10:02:53 +0000 (UTC) (envelope-from kostikbel@gmail.com) Received: from tom.home (kib@localhost [127.0.0.1]) by kib.kiev.ua (8.15.2/8.15.2) with ESMTPS id u5MA2ggC018605 (version=TLSv1 cipher=DHE-RSA-CAMELLIA256-SHA bits=256 verify=NO); Wed, 22 Jun 2016 13:02:42 +0300 (EEST) (envelope-from kostikbel@gmail.com) DKIM-Filter: OpenDKIM Filter v2.10.3 kib.kiev.ua u5MA2ggC018605 Received: (from kostik@localhost) by tom.home (8.15.2/8.15.2/Submit) id u5MA2fPD018604; Wed, 22 Jun 2016 13:02:41 +0300 (EEST) (envelope-from kostikbel@gmail.com) X-Authentication-Warning: tom.home: kostik set sender to kostikbel@gmail.com using -f Date: Wed, 22 Jun 2016 13:02:41 +0300 From: Konstantin Belousov To: Maxim Sobolev Cc: John Baldwin , Adrian Chadd , Alan Somers , Alan Cox , Alan Cox , freebsd-current , performance@freebsd.org, "current@freebsd.org" Subject: Re: PostgreSQL performance on FreeBSD Message-ID: <20160622100241.GM38613@kib.kiev.ua> References: <20140627125613.GT93733@kib.kiev.ua> <1603235.2ShtoCfSqO@ralph.baldwin.cx> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.6.1 (2016-04-27) X-Spam-Status: No, score=-2.0 required=5.0 tests=ALL_TRUSTED,BAYES_00, DKIM_ADSP_CUSTOM_MED,FREEMAIL_FROM,NML_ADSP_CUSTOM_MED autolearn=no autolearn_force=no version=3.4.1 X-Spam-Checker-Version: SpamAssassin 3.4.1 (2015-04-28) on tom.home X-BeenThere: freebsd-performance@freebsd.org X-Mailman-Version: 2.1.22 Precedence: list List-Id: Performance/tuning List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Wed, 22 Jun 2016 10:02:54 -0000 On Tue, Jun 21, 2016 at 12:48:00PM -0700, Maxim Sobolev wrote: > Thanks, Konstantin for the great work, we are definitely looking forward to > get all those improvements to be part of the default FreeBSD kernel/port. > Would be nice if you can post an update some day later as to what's > integrated and what's not. I did posted the update several days earlier. Since you replying to this thread, it would be not unreasonable to read recent messages that were sent. > > Just in case, I've opened #14206 with PG to switch us to using POSIX > semaphores by default. Apart from the mentioned performance benefits, SYSV > semaphores are PITA to deal with as they come in very limited quantities by > default. Also they might stay around if PG dies/gets nuked and prevent it > from starting again due to overflow. We've got some quite ugly code to > clean up those using ipcrm(1) in our build scripts to deal with just that. > I am happy that code could be retired now. Named semaphores also stuck around if processes are killed without cleanup.