Received: from malur.postgresql.org ([217.196.149.56]) by arkaria.postgresql.org with esmtp (Exim 4.80) (envelope-from ) id 1ZgxXb-0004yF-5Q for pgsql-performance@arkaria.postgresql.org; Tue, 29 Sep 2015 16:14:07 +0000 Received: from localhost ([127.0.0.1] helo=postgresql.org) by malur.postgresql.org with smtp (Exim 4.84) (envelope-from ) id 1ZgxXa-0000lb-Me for pgsql-performance@arkaria.postgresql.org; Tue, 29 Sep 2015 16:14:06 +0000 Received: from magus.postgresql.org ([2a02:c0:301:0:ffff::29]) by malur.postgresql.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_CBC_SHA384:256) (Exim 4.84) (envelope-from ) id 1ZgxVx-0007Ld-H3 for pgsql-performance@postgresql.org; Tue, 29 Sep 2015 16:12:25 +0000 Received: from proofpoint1.mail.rice.edu ([128.42.201.100] helo=pp1.rice.edu) by magus.postgresql.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_CBC_SHA384:256) (Exim 4.84) (envelope-from ) id 1ZgxVs-0002z0-O9 for pgsql-performance@postgresql.org; Tue, 29 Sep 2015 16:12:24 +0000 Received: from pps.filterd (pp1.rice.edu [127.0.0.1]) by pp1.rice.edu (8.15.0.59/8.15.0.59) with SMTP id t8TG9BAP002236; Tue, 29 Sep 2015 11:12:17 -0500 Received: from mh10.mail.rice.edu (mh10.mail.rice.edu [128.42.201.30]) by pp1.rice.edu with ESMTP id 1x5n619qpy-1; Tue, 29 Sep 2015 11:12:17 -0500 X-Virus-Scanned: by amavis-2.7.0 at mh10.mail.rice.edu, auth channel X-SMTP-Auth: no X-SMTP-Auth: no Received: from aart.rice.edu (aart.rice.edu [168.7.56.48]) by mh10.mail.rice.edu (Postfix) with ESMTP id ADFD661165; Tue, 29 Sep 2015 11:12:16 -0500 (CDT) Received: by aart.rice.edu (Postfix, from userid 18612) id A632D100839; Tue, 29 Sep 2015 11:12:16 -0500 (CDT) Date: Tue, 29 Sep 2015 11:12:16 -0500 From: "ktm@rice.edu" To: Bertrand Paquet Cc: pgsql-performance@postgresql.org Subject: Re: Performance problem with gin index Message-ID: <20150929161216.GU30163@aart.rice.edu> References: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.5.20 (2009-12-10) X-Proofpoint-Spam-Details: rule=notspam policy=default score=0 kscore.is_bulkscore=0 kscore.compositescore=1 compositescore=0.9 suspectscore=0 malwarescore=0 phishscore=0 bulkscore=0 kscore.is_spamscore=0 rbsscore=0.9 spamscore=0 urlsuspectscore=0.9 adultscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.0.1-1507310000 definitions=main-1509290187 X-Pg-Spam-Score: -4.2 (----) 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 On Tue, Sep 29, 2015 at 05:45:41PM +0200, Bertrand Paquet wrote: > Hi, > > We have got big slow down on our production plateform (PG 9.4.4). > After analyzing wals with pg_xlogdump, we see lot of writing in Gin Indexes. > We suspect slow down are related to the write of pending update on the > index. > > So, is there any method to see > - what is the current config of gin_pending_list_limit on a given index ? > - the current size of pending list on a given index ? > > Regards, > Bertrand Hi Bertrand, You might try disabling fastupdate for the index. 9.5 has some work in this area, but prior to that disabling it is the best fix. It certainly helped our system with the same issue. Regards, Ken -- Sent via pgsql-performance mailing list (pgsql-performance@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-performance