Received: from localhost (unknown [200.46.204.183]) by postgresql.org (Postfix) with ESMTP id 2C5CD2E017D for ; Tue, 26 Feb 2008 19:36:25 -0400 (AST) Received: from postgresql.org ([200.46.204.71]) by localhost (mx1.hub.org [200.46.204.183]) (amavisd-maia, port 10024) with ESMTP id 21437-01-10 for ; Tue, 26 Feb 2008 19:36:22 -0400 (AST) X-Greylist: from auto-whitelisted by SQLgrey-1.7.5 Received: from sss.pgh.pa.us (sss.pgh.pa.us [66.207.139.130]) by postgresql.org (Postfix) with ESMTP id 84CBC2E01B0 for ; Tue, 26 Feb 2008 19:33:55 -0400 (AST) Received: from sss2.sss.pgh.pa.us (tgl@localhost [127.0.0.1]) by sss.pgh.pa.us (8.14.2/8.14.2) with ESMTP id m1QNXoQ8009941; Tue, 26 Feb 2008 18:33:50 -0500 (EST) To: James Mansion cc: Joel Stevenson , pgsql-performance@postgresql.org Subject: Re: LISTEN / NOTIFY performance in 8.3 In-reply-to: <47C48F9E.7000505@mansionfamily.plus.com> References: <5576.1203795335@sss.pgh.pa.us> <6730.1203829093@sss.pgh.pa.us> <5080.1204047806@sss.pgh.pa.us> <47C48F9E.7000505@mansionfamily.plus.com> Comments: In-reply-to James Mansion message dated "Tue, 26 Feb 2008 22:15:58 +0000" Date: Tue, 26 Feb 2008 18:33:50 -0500 Message-ID: <9940.1204068830@sss.pgh.pa.us> From: Tom Lane X-Virus-Scanned: Maia Mailguard 1.0.1 X-Archive-Number: 200802/360 X-Sequence-Number: 28902 James Mansion writes: > I certainly hadn't expected that to be the implementation technique - > isn't it smply that we need > a sngle flag per worker process and can set/test-and-clear with atomic > operations and then a > signal to wake them up? Hardly --- how's that going to pass a notify name? Also, a lot of people want some payload data in a notify, not just a condition name; any reimplementation that doesn't address that desire probably won't get accepted. There's lots of threads in the -hackers archives about reimplementing listen/notify in a saner fashion. Personally I lean towards using something much like the sinval queue. regards, tom lane