Received: from malur.postgresql.org ([217.196.149.56]) by arkaria.postgresql.org with esmtp (Exim 4.84_2) (envelope-from ) id 1eYyqU-0000Ub-En for pgsql-general@arkaria.postgresql.org; Tue, 09 Jan 2018 18:41:58 +0000 Received: from localhost ([127.0.0.1] helo=malur.postgresql.org) by malur.postgresql.org with esmtp (Exim 4.84_2) (envelope-from ) id 1eYyqU-0001Az-2A for pgsql-general@arkaria.postgresql.org; Tue, 09 Jan 2018 18:41:58 +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_2) (envelope-from ) id 1eYyqT-0001Aq-Ny for pgsql-general@lists.postgresql.org; Tue, 09 Jan 2018 18:41:57 +0000 Received: from smtprelay0243.b.hostedemail.com ([64.98.42.243] helo=smtprelay.b.hostedemail.com) by makus.postgresql.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_CBC_SHA384:256) (Exim 4.89) (envelope-from ) id 1eYyqR-0003jK-16 for pgsql-general@lists.postgresql.org; Tue, 09 Jan 2018 18:41:56 +0000 Received: from filter.hostedemail.com (10.5.19.248.rfc1918.com [10.5.19.248]) by smtprelay01.b.hostedemail.com (Postfix) with ESMTP id 6A4662D2A11; Tue, 9 Jan 2018 18:41:53 +0000 (UTC) X-Session-Marker: 616C76686572726540616C76682E6E6F2D69702E6F7267 X-Spam-Summary: 50,0,0,,d41d8cd98f00b204,alvherre@alvh.no-ip.org,:::::,RULES_HIT:41:355:379:599:967:973:988:989:1260:1277:1311:1312:1313:1314:1345:1359:1437:1515:1516:1518:1519:1534:1538:1568:1593:1594:1595:1596:1711:1714:1730:1747:1777:1792:2393:2525:2560:2563:2682:2685:2691:2828:2859:2912:2933:2937:2939:2942:2945:2947:2951:2954:3022:3138:3139:3140:3141:3142:3865:3867:3868:3871:3872:3873:3874:3934:3936:3938:3941:3944:3947:3950:3953:3956:3959:4605:5007:6119:6261:9025:9121:10004:10400:10848:11232:11658:11914:13069:13311:13357:13439:13894:13895:14764:21067:21080:21627:30054,0,RBL:none,CacheIP:none,Bayesian:0.5,0.5,0.5,Netcheck:none,DomainCache:0,MSF:not bulk,SPF:,MSBL:0,DNSBL:none,Custom_rules:0:0:0,LFtime:4,LUA_SUMMARY:none X-HE-Tag: sand85_2d67d89f2e81b X-Filterd-Recvd-Size: 1447 Received: from alvin.alvh.no-ip.org (unknown [179.57.113.18]) (Authenticated sender: alvherre@alvh.no-ip.org) by omf08.b.hostedemail.com (Postfix) with ESMTPA; Tue, 9 Jan 2018 18:41:51 +0000 (UTC) Received: by alvin.alvh.no-ip.org (Postfix, from userid 1000) id 7954B880; Tue, 9 Jan 2018 15:41:49 -0300 (-03) Date: Tue, 9 Jan 2018 15:41:49 -0300 From: Alvaro Herrera To: Rakesh Kumar Cc: Stephen Frost , "pgsql-general@lists.postgresql.org" Subject: Re: data-checksums Message-ID: <20180109184149.ih4ore4c4axwizor@alvherre.pgsql> MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: User-Agent: NeoMutt/20170306-137-4415bd-dirty (1.8.0) List-Id: List-Help: List-Subscribe: List-Post: List-Owner: List-Archive: Precedence: bulk Rakesh Kumar wrote: > > > That said, imv anyway, the performance hit is small and having > > checksums is well worth it. > > I also would like to believe that the hit is small, but when PG > official document writes "noticeable performance penalty", it becomes > difficult to convince management that the hit is small :-) Why believe, when you can measure? -- Álvaro Herrera https://www.2ndQuadrant.com/ PostgreSQL Development, 24x7 Support, Remote DBA, Training & Services