Received: from localhost (wm.hub.org [200.46.204.128]) by postgresql.org (Postfix) with ESMTP id B0B619FB635 for ; Mon, 9 Oct 2006 11:15:41 -0300 (ADT) Received: from postgresql.org ([200.46.204.71]) by localhost (mx1.hub.org [200.46.204.128]) (amavisd-new, port 10024) with ESMTP id 60885-06 for ; Mon, 9 Oct 2006 14:15:33 +0000 (UTC) X-Greylist: from auto-whitelisted by SQLgrey- Received: from sss.pgh.pa.us (sss.pgh.pa.us [66.207.139.130]) by postgresql.org (Postfix) with ESMTP id DC3F69FB624 for ; Mon, 9 Oct 2006 11:15:32 -0300 (ADT) Received: from sss2.sss.pgh.pa.us (tgl@localhost [127.0.0.1]) by sss.pgh.pa.us (8.13.6/8.13.6) with ESMTP id k99EFN5M001601; Mon, 9 Oct 2006 10:15:23 -0400 (EDT) To: Kyle Bateman cc: pgsql-sql@postgresql.org Subject: Re: PG 8.2beta reordering working for this case? In-reply-to: <4529DDCC.6010909@actarg.com> References: <44DF6582.4000806@actarg.com> <82mza77rch.fsf@mid.bfk.de> <44E11E1A.8020507@actarg.com> <27367.1155606817@sss.pgh.pa.us> <44E349BA.4070205@actarg.com> <26676.1155747492@sss.pgh.pa.us> <44E3840E.4080502@actarg.com> <45284DBC.3060901@actarg.com> <25779.1160329771@sss.pgh.pa.us> <4529DDCC.6010909@actarg.com> Comments: In-reply-to Kyle Bateman message dated "Sun, 08 Oct 2006 23:27:40 -0600" Date: Mon, 09 Oct 2006 10:15:23 -0400 Message-ID: <1600.1160403323@sss.pgh.pa.us> From: Tom Lane X-Virus-Scanned: Maia Mailguard 1.0.1 X-Archive-Number: 200610/92 X-Sequence-Number: 26481 Kyle Bateman writes: > BTW, explain analyze still says 10 seconds of run time (and takes 10 > seconds to run), but when I remove the explain analyze, the query runs > in about a second. What's that all about? Instrumentation overhead ... you're probably running this on a PC with a very slow clock-reading capability. Each node output row counted by explain analyze takes two gettimeofday() calls, and apparently it's not unusual for those to take several microseconds on cheap motherboards, even when the CPU is nominally very fast. regards, tom lane