Received: from malur.postgresql.org ([217.196.149.56]) by arkaria.postgresql.org with esmtp (Exim 4.80) (envelope-from ) id 1ZJjCq-00073J-Ti for pgsql-hackers@arkaria.postgresql.org; Mon, 27 Jul 2015 14:16:41 +0000 Received: from localhost ([127.0.0.1] helo=postgresql.org) by malur.postgresql.org with smtp (Exim 4.84) (envelope-from ) id 1ZJjCq-0000Ur-GK for pgsql-hackers@arkaria.postgresql.org; Mon, 27 Jul 2015 14:16:40 +0000 Received: from makus.postgresql.org ([2001:4800:1501:1::229]) by malur.postgresql.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_CBC_SHA384:256) (Exim 4.84) (envelope-from ) id 1ZJj98-0008Ea-HR for pgsql-hackers@postgresql.org; Mon, 27 Jul 2015 14:12:50 +0000 Received: from smtp-auth.no-ip.com ([8.23.224.61] helo=out.smtp-auth.no-ip.com) by makus.postgresql.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:256) (Exim 4.84) (envelope-from ) id 1ZJj93-0006vm-9s for pgsql-hackers@postgresql.org; Mon, 27 Jul 2015 14:12:49 +0000 X-No-IP: alvh.no-ip.org@noip-smtp X-Report-Spam-To: abuse@no-ip.com Received: from alvin.alvh.no-ip.org (unknown [181.42.250.3]) (Authenticated sender: alvh.no-ip.org@noip-smtp) by smtp-auth.no-ip.com (Postfix) with ESMTPA id F34CB40058B; Mon, 27 Jul 2015 07:12:38 -0700 (PDT) Received: by alvin.alvh.no-ip.org (Postfix, from userid 1000) id 79E011123; Mon, 27 Jul 2015 16:12:31 +0200 (CEST) Date: Mon, 27 Jul 2015 11:12:31 -0300 From: Alvaro Herrera To: Noah Misch Cc: Peter Geoghegan , Simon Riggs , Bruce Momjian , Andres Freund , Robert Haas , Tom Lane , Stephen Frost , Magnus Hagander , "pgsql-hackers@postgresql.org" Subject: Re: Restore-reliability mode Message-ID: <20150727141231.GE5596@postgresql.org> References: <20150530154559.GA25053@momjian.us> <20150530204727.GJ13944@alap3.anarazel.de> <20150531024845.GB13697@momjian.us> <20150603135049.GA74753@tornado.leadboat.com> <20150606195805.GA118899@tornado.leadboat.com> <20150723195349.GW5596@postgresql.org> <20150726072645.GF1452488@tornado.leadboat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <20150726072645.GF1452488@tornado.leadboat.com> User-Agent: Mutt/1.5.23 (2014-03-12) X-Pg-Spam-Score: -2.6 (--) List-Archive: List-Help: List-ID: List-Owner: List-Post: List-Subscribe: List-Unsubscribe: X-Mailing-List: pgsql-hackers Precedence: bulk Sender: pgsql-hackers-owner@postgresql.org Noah Misch wrote: > On Thu, Jul 23, 2015 at 04:53:49PM -0300, Alvaro Herrera wrote: > > Peter Geoghegan wrote: > > > On Sat, Jun 6, 2015 at 12:58 PM, Noah Misch wrote: > > > > - Call VALGRIND_MAKE_MEM_NOACCESS() on a shared buffer when its local pin > > > > count falls to zero. Under CLOBBER_FREED_MEMORY, wipe a shared buffer > > > > when its global pin count falls to zero. > > > > > > Did a patch for this ever materialize? > > > > I think the first part would be something like the attached. > > Neat. Does it produce any new complaints during "make installcheck"? I only tried a few tests, for lack of time, and it didn't produce any. (To verify that the whole thing was working properly, I reduced the range of memory made available during PinBuffer and that resulted in a crash immediately). I am not really familiar with valgrind TBH and just copied a recipe to run postmaster under it, so if someone with more valgrind-fu could verify this, it would be great. This part: > > > > Under CLOBBER_FREED_MEMORY, wipe a shared buffer when its > > > > global pin count falls to zero. can be done without any valgrind, I think. Any takers? -- Álvaro Herrera http://www.2ndQuadrant.com/ PostgreSQL Development, 24x7 Support, Remote DBA, Training & Services -- Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers