Received: from magus.postgresql.org (magus.postgresql.org [87.238.57.229]) by mail.postgresql.org (Postfix) with ESMTP id 11AD396BB2C for ; Thu, 19 Jul 2012 23:27:55 -0300 (ADT) Received: from mail-yx0-f174.google.com ([209.85.213.174]) by magus.postgresql.org with esmtp (Exim 4.72) (envelope-from ) id 1Ss2wZ-0003q2-3j for pgsql-performance@postgresql.org; Fri, 20 Jul 2012 02:27:54 +0000 Received: by yenl2 with SMTP id l2so3541398yen.19 for ; Thu, 19 Jul 2012 19:27:36 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=from:to:subject:date:message-id:mime-version:content-type :content-transfer-encoding:x-mailer:thread-index:content-language; bh=veKpRLTO8vPq6/zGuqaCU/nOYhLzNaraDZkSW+x/Vo8=; b=n8Q1KfOkabezg7dF5qOWVjvdGLld748hkwJucSbQGvfQyp+rqCzYXFj1qS0nIvSQre FSFNN59h7CVUgbLy7kRBMWGol6ja/5ugAvBTpxkRF3HGSHL2adrxkZYqx28ANt93goxR us0RrQyTxUj7fzXE96W/MA6pQP5WxTnIN2+MCn1HzEM61lY9vilv88STx0HoTMtBbicm Enck3FmAwYFyK1MFaNLEquF2lLfO9MmYRTfrCGcbsJVT8gdzrsr5OJlOsokC5RwxSST4 KKF3JjfceMS+On6HTbLJkzlzbfEO7WcX3/BjD6KCvbvKifa4QsJqXQWApKWMwV+v4nd0 x0SA== Received: by 10.50.236.70 with SMTP id us6mr3158632igc.8.1342751256034; Thu, 19 Jul 2012 19:27:36 -0700 (PDT) Received: from Duality (65-128-10-123.hlrn.qwest.net. [65.128.10.123]) by mx.google.com with ESMTPS id ua2sm6691679igb.7.2012.07.19.19.27.33 (version=SSLv3 cipher=OTHER); Thu, 19 Jul 2012 19:27:34 -0700 (PDT) From: "mark" To: Subject: Deferred constraints performance impact ? Date: Thu, 19 Jul 2012 20:27:38 -0600 Message-ID: <01a701cd661f$3cc05770$b6410650$@com> MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit X-Mailer: Microsoft Office Outlook 12.0 thread-index: Ac1mHzskbG+ikl8FTkWR4ws02ldkVw== Content-Language: en-us X-Pg-Spam-Score: -1.3 (-) X-Archive-Number: 201207/239 X-Sequence-Number: 47420 Hi all, We have put some deferred constraints (some initially immediate, some initially deferred) into our database for testing with our applications. I haven't seen any noticeable loss in performance, but I am not sure I can properly simulate our full production environment load levels in my tests. I was wondering if I am turning on something that has known significant negative impacts to performance, just from having them there. I understand a lot more may have to be tracked through a transaction and there could be some impact from that. Similar to an after update trigger? Or are the two not comparable in terms of impact from what is tracked and then checked. Anyways, just looking for feedback if anyone has any. -Mark