Received: from malur.postgresql.org ([217.196.149.56]) by arkaria.postgresql.org with esmtp (Exim 4.80) (envelope-from ) id 1WQdkY-0002I4-0j for pgsql-performance@arkaria.postgresql.org; Thu, 20 Mar 2014 14:15:14 +0000 Received: from localhost ([127.0.0.1] helo=postgresql.org) by malur.postgresql.org with smtp (Exim 4.80) (envelope-from ) id 1WQdkX-0004hu-E2 for pgsql-performance@arkaria.postgresql.org; Thu, 20 Mar 2014 14:15:13 +0000 Received: from magus.postgresql.org ([2a02:c0:301:0:ffff::29]) by malur.postgresql.org with esmtp (Exim 4.80) (envelope-from ) id 1WQdkW-0004hi-Lg for pgsql-performance@postgresql.org; Thu, 20 Mar 2014 14:15:12 +0000 Received: from sss.pgh.pa.us ([66.207.139.130]) by magus.postgresql.org with esmtp (Exim 4.80) (envelope-from ) id 1WQdkP-0004v4-NK for pgsql-performance@postgresql.org; Thu, 20 Mar 2014 14:15:12 +0000 Received: from sss1.sss.pgh.pa.us (localhost [127.0.0.1]) by sss.pgh.pa.us (8.14.4/8.14.4) with ESMTP id s2KEF3Ob002751; Thu, 20 Mar 2014 10:15:03 -0400 From: Tom Lane To: Franck Routier cc: pgsql-performance@postgresql.org Subject: Re: long lasting select, no io nor cpu usage ? In-reply-to: <532AF623.2040502@axege.com> References: <532AF271.4040903@axege.com> <2042.1395323785@sss.pgh.pa.us> <532AF623.2040502@axege.com> Comments: In-reply-to Franck Routier message dated "Thu, 20 Mar 2014 15:07:31 +0100" Date: Thu, 20 Mar 2014 10:15:03 -0400 Message-ID: <2749.1395324903@sss.pgh.pa.us> X-Pg-Spam-Score: -1.9 (-) List-Archive: List-Help: List-ID: List-Owner: List-Post: List-Subscribe: List-Unsubscribe: X-Mailing-List: pgsql-performance Precedence: bulk Sender: pgsql-performance-owner@postgresql.org Franck Routier writes: > Le 20/03/2014 14:56, Tom Lane a écrit : >> pg_locks, probably. regards, tom lane > select * from pg_stat_activity shows 'F'alse in the waiting column for > the query. Hm. The next most likely theory is that it's waiting on network I/O, but it's hard to tell that from the outside. Can you attach to the stuck backend with gdb and get a stack trace? http://wiki.postgresql.org/wiki/Generating_a_stack_trace_of_a_PostgreSQL_backend regards, tom lane -- Sent via pgsql-performance mailing list (pgsql-performance@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-performance