Received: from malur.postgresql.org ([217.196.149.56]) by arkaria.postgresql.org with esmtp (Exim 4.80) (envelope-from ) id 1WhCNo-0005sr-Ov for pgsql-hackers@arkaria.postgresql.org; Mon, 05 May 2014 06:28:12 +0000 Received: from localhost ([127.0.0.1] helo=postgresql.org) by malur.postgresql.org with smtp (Exim 4.80) (envelope-from ) id 1WhCNo-00019f-67 for pgsql-hackers@arkaria.postgresql.org; Mon, 05 May 2014 06:28:12 +0000 Received: from magus.postgresql.org ([2a02:c0:301:0:ffff::29]) by malur.postgresql.org with esmtp (Exim 4.80) (envelope-from ) id 1WhCNn-00019G-1N for pgsql-hackers@postgresql.org; Mon, 05 May 2014 06:28:11 +0000 Received: from [2404:130:0:10::40:2] (helo=mail.catalyst.net.nz) by magus.postgresql.org with esmtp (Exim 4.80) (envelope-from ) id 1WhCNg-0001df-Po for pgsql-hackers@postgresql.org; Mon, 05 May 2014 06:28:09 +0000 Received: from localhost (localhost [127.0.0.1]) by mail.catalyst.net.nz (Postfix) with ESMTP id A20B067669; Mon, 5 May 2014 18:27:58 +1200 (NZST) X-Virus-Scanned: Debian amavisd-new at catalyst.net.nz Received: from mail.catalyst.net.nz ([127.0.0.1]) by localhost (bertrand.catalyst.net.nz [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id qnLMOBVy4Z2U; Mon, 5 May 2014 18:27:48 +1200 (NZST) Received: from [192.168.1.64] (122-60-64-230.jetstream.xtra.co.nz [122.60.64.230]) (Authenticated sender: mark.kirkwood) by mail.catalyst.net.nz (Postfix) with ESMTPSA id DBF15333C7; Mon, 5 May 2014 18:27:47 +1200 (NZST) Message-ID: <53672F63.3080400@catalyst.net.nz> Date: Mon, 05 May 2014 18:27:47 +1200 From: Mark Kirkwood User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:24.0) Gecko/20100101 Thunderbird/24.5.0 MIME-Version: 1.0 To: Amit Kapila , Haribabu Kommi CC: Alvaro Herrera , "pgsql-hackers@postgresql.org" Subject: Re: Per table autovacuum vacuum cost limit behaviour strange References: <52FACF15.8020507@catalyst.net.nz> <52FC4AA6.50803@catalyst.net.nz> <20140214213227.GF6342@eldon.alvh.no-ip.org> In-Reply-To: Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit X-Host-Lookup-Failed: Reverse DNS lookup failed for 2404:130:0:10::40:2 (failed) X-Pg-Spam-Score: -1.1 (-) List-Archive: List-Help: List-ID: List-Owner: List-Post: List-Subscribe: List-Unsubscribe: X-Mailing-List: pgsql-hackers Precedence: bulk Sender: pgsql-hackers-owner@postgresql.org On 05/05/14 15:22, Amit Kapila wrote: > Here what I could understand is that sum of cost_limit for all > autovacuum workers should never exceed the value of > autovacuum_vacuum_cost_limit which seems to be always the > case in current code but same is not true for proposed patch. > Right, but have a look at the 1st message in this thread - the current behavior (and to a large extent the above condition) means that setting cost limits per table does not work in any remotely intuitive way. ITSM that the whole purpose of a per table setting in this context is to override the behavior of auto vacuum throttling - and currently this does not happen unless you get real brutal (i.e setting the cost delay to zero in addition to setting cost limit...making the whole cost limit a bit pointless). regards Mark -- Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers