Received: from localhost (wm.hub.org [200.46.204.128]) by postgresql.org (Postfix) with ESMTP id A9D6B9FB2F4 for ; Tue, 10 Oct 2006 14:50:02 -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 01180-01 for ; Tue, 10 Oct 2006 17:49:56 +0000 (UTC) X-Greylist: from auto-whitelisted by SQLgrey- Received: from lynet.oppetid.no (oppetid.no [80.65.51.2]) by postgresql.org (Postfix) with ESMTP id 918AA9FB2CC for ; Tue, 10 Oct 2006 14:49:56 -0300 (ADT) Received: by lynet.oppetid.no (Postfix, from userid 1019) id 45CD5119EF0; Tue, 10 Oct 2006 19:49:55 +0200 (CEST) Date: Tue, 10 Oct 2006 19:49:55 +0200 From: Tobias Brox To: Tom Lane Cc: Tobias Brox , pgsql-performance@postgresql.org Subject: Re: long running transactions Message-ID: <20061010174955.GA284@oppetid.no> References: <20061010161027.GA18908@oppetid.no> <25404.1160497420@sss.pgh.pa.us> <20061010163913.GA8097@oppetid.no> <20061010164142.GA5360@oppetid.no> <25631.1160498572@sss.pgh.pa.us> <20061010170639.GB5360@oppetid.no> <25953.1160500192@sss.pgh.pa.us> <20061010171304.GC5360@oppetid.no> <26123.1160500707@sss.pgh.pa.us> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <26123.1160500707@sss.pgh.pa.us> Organization: Group Nordicbet User-Agent: Mutt/1.5.9i X-Virus-Scanned: Maia Mailguard 1.0.1 X-Spam-Status: No, hits=0.135 tagged_above=0 required=5 tests=FORGED_RCVD_HELO X-Spam-Level: X-Archive-Number: 200610/202 X-Sequence-Number: 21331 [Tom Lane - Tue at 01:18:27PM -0400] > >> Hmph. Is the autovac process actually doing anything (strace would be > >> revealing)? It's definitively doing something; mostly reading, but also some few writes, semops and opens. > If not, can you attach to the autovac process with gdb and > >> get a stack trace to see where it's blocked? (gdb) bt #0 0xb7c599f8 in select () from /lib/tls/libc.so.6 #1 0x08253c53 in pg_usleep () #2 0x0812ee93 in vacuum_delay_point () #3 0x0812f2a5 in lazy_vacuum_rel () #4 0x0812ef7b in lazy_vacuum_rel () #5 0x0812b4b6 in vac_update_relstats () #6 0x0812a995 in vacuum () #7 0x0818d2ca in autovac_stopped () #8 0x0818ceae in autovac_stopped () #9 0x0818c848 in autovac_stopped () #10 0x0818c4e2 in autovac_start () #11 0x08192c11 in PostmasterMain () #12 0x08191dcf in PostmasterMain () #13 0x081541b1 in main () > It'll come back after the autovacuum naptime. If it gets stuck again, > please investigate. It seems stuck, has had the same transid for a long while, and the number of undeletable dead rows in our tables are increasing.