Received: from malur.postgresql.org ([217.196.149.56]) by arkaria.postgresql.org with esmtps (TLS1.3:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.92) (envelope-from ) id 1lFiHP-0001vf-90 for pgsql-hackers@arkaria.postgresql.org; Fri, 26 Feb 2021 18:55:59 +0000 Received: from localhost ([127.0.0.1] helo=malur.postgresql.org) by malur.postgresql.org with esmtp (Exim 4.92) (envelope-from ) id 1lFiHO-0006UY-7B for pgsql-hackers@arkaria.postgresql.org; Fri, 26 Feb 2021 18:55:58 +0000 Received: from magus.postgresql.org ([2a02:c0:301:0:ffff::29]) by malur.postgresql.org with esmtps (TLS1.3:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.92) (envelope-from ) id 1lFiHO-0006UR-0S for pgsql-hackers@lists.postgresql.org; Fri, 26 Feb 2021 18:55:58 +0000 Received: from sss.pgh.pa.us ([66.207.139.130]) by magus.postgresql.org with esmtps (TLS1.3:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.92) (envelope-from ) id 1lFiHM-0000Jh-02 for pgsql-hackers@lists.postgresql.org; Fri, 26 Feb 2021 18:55:57 +0000 Received: from sss1.sss.pgh.pa.us (localhost [127.0.0.1]) by sss.pgh.pa.us (8.15.2/8.15.2) with ESMTP id 11QItAnw351244; Fri, 26 Feb 2021 13:55:11 -0500 From: Tom Lane To: "Joel Jacobson" cc: "Chapman Flack" , pgsql-hackers@lists.postgresql.org Subject: Re: Some regular-expression performance hacking In-reply-to: <0e3addb8-415a-4e94-8294-c7ab86ad46d0@www.fastmail.com> References: <1340281.1613018383@sss.pgh.pa.us> <85140bfb-516c-449b-8a03-7930abb42b88@www.fastmail.com> <1813969.1613250697@sss.pgh.pa.us> <913516b8-c3d7-4dea-bf60-d735cf4673f1@www.fastmail.com> <2155152.1613358697@sss.pgh.pa.us> <99f6cbe0-6e58-4e41-add0-977271a5cf84@www.fastmail.com> <2752386.1613595636@sss.pgh.pa.us> <5deabab3-a335-4b57-a046-8a9ad8f2f142@www.fastmail.com> <12e6381c-adc1-4711-a619-864fb8df969c@www.fastmail.com> <2840118.1613671847@sss.pgh.pa.us> <2845172.1613674385@sss.pgh.pa.us> <3028106.1613748380@sss.pgh.pa.us> <60319BDB.2040302@anastigmatix.net> <3374539.1613870009@sss.pgh.pa.us> <4019408.1614133970@sss.pgh.pa.us> <4185677.1614208792@sss.pgh.pa.us> <168861.1614298592@sss.pgh.pa.us> <0e3addb8-415a-4e94-8294-c7ab86ad46d0@www.fastmail.com> Comments: In-reply-to "Joel Jacobson" message dated "Fri, 26 Feb 2021 17:42:32 +0100" MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-ID: <351242.1614365710.1@sss.pgh.pa.us> Date: Fri, 26 Feb 2021 13:55:10 -0500 Message-ID: <351243.1614365710@sss.pgh.pa.us> List-Id: List-Help: List-Subscribe: List-Post: List-Owner: List-Archive: Precedence: bulk "Joel Jacobson" writes: > On Fri, Feb 26, 2021, at 01:16, Tom Lane wrote: >> 0007-smarter-regex-allocation-2.patch > I've successfully tested this patch. Cool, thanks for testing! > That's a 29% speed-up compared to HEAD! Truly amazing. Hmm, I'm still only seeing about 10% or a little better. I wonder why the difference in your numbers. Either way, though, I'll take it, since the main point here is to cut memory consumption and not so much cycles. regards, tom lane