Received: from malur.postgresql.org ([217.196.149.56]) by arkaria.postgresql.org with esmtp (Exim 4.80) (envelope-from ) id 1Vk8H9-0000t1-4e for pgsql-general@arkaria.postgresql.org; Sat, 23 Nov 2013 08:09:11 +0000 Received: from localhost ([127.0.0.1] helo=postgresql.org) by malur.postgresql.org with smtp (Exim 4.80) (envelope-from ) id 1Vk8H8-0002I9-IV for pgsql-general@arkaria.postgresql.org; Sat, 23 Nov 2013 08:09:10 +0000 Received: from makus.postgresql.org ([2001:4800:7903:4::125]) by malur.postgresql.org with esmtp (Exim 4.80) (envelope-from ) id 1Vk8H6-0002GF-Ks for pgsql-general@postgresql.org; Sat, 23 Nov 2013 08:09:08 +0000 Received: from mail-wg0-x22d.google.com ([2a00:1450:400c:c00::22d]) by makus.postgresql.org with esmtp (Exim 4.80) (envelope-from ) id 1Vk8H4-0004sm-Dd for pgsql-general@postgresql.org; Sat, 23 Nov 2013 08:09:08 +0000 Received: by mail-wg0-f45.google.com with SMTP id y10so207498wgg.24 for ; Sat, 23 Nov 2013 00:09:05 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=mime-version:in-reply-to:references:date:message-id:subject:from:to :cc:content-type; bh=AOqpIlYX/7ACHixvZTD4nknwM/7vKYMsQel7Fh56VrM=; b=u549QOGI1pZwzRJpv2s79DoN5/7DuJ9Z4BGQs6iSWb1Z3WJyc6+Gj3OmY50P5Q9cit IHYtRUbBrkHtUHBVliVKco3qpNl3q9KEzc57yOMnZQ4RJVMIs7SuxPaclw8dkwwWPAax yfXoByIkbRYZCWAmMe7zDLz7OhCCGN+fvQNAhGnqdVyu8PEI8NVbjZmisd89L8GBQxk0 nvrBvpuJ6lUnCsEieib58QLKEr2FF0a8Veq71xRrf2TLyFWYOqQOGx+ql32mY22jGoP8 JQoUWj1DV+t78SSic0439dmXuhH+NheyZEQ5qv1zaiH4pD93Bn+3JNQhVsX8rWHp1L/9 xPxA== MIME-Version: 1.0 X-Received: by 10.194.206.5 with SMTP id lk5mr347611wjc.46.1385194145023; Sat, 23 Nov 2013 00:09:05 -0800 (PST) Received: by 10.180.75.111 with HTTP; Sat, 23 Nov 2013 00:09:04 -0800 (PST) In-Reply-To: References: <528F4BE2.7000400@gmx.net> Date: Sat, 23 Nov 2013 17:09:04 +0900 Message-ID: Subject: Re: PG replication across DataCenters From: Michael Paquier To: Albe Laurenz Cc: Kaushal Shriyan , =?ISO-8859-1?Q?Torsten_F=F6rtsch_=2AEXTERN=2A?= , "pgsql-general@postgresql.org" Content-Type: text/plain; charset=ISO-8859-1 X-Pg-Spam-Score: -2.0 (--) List-Archive: List-Help: List-ID: List-Owner: List-Post: List-Subscribe: List-Unsubscribe: X-Mailing-List: pgsql-general Precedence: bulk Sender: pgsql-general-owner@postgresql.org On Fri, Nov 22, 2013 at 11:46 PM, Albe Laurenz wrote: > Michael Paquier wrote: >> On Fri, Nov 22, 2013 at 10:03 PM, Kaushal Shriyan wrote: >>> I am not sure i understand the difference between async and sync replication >>> and on what scenarios i should use async or sync replication. Does it mean >>> if it is within same DC then sync replication is the best and if it is >>> across DC replication async is better than sync. Please help me understand. > >> In the case of synchronous replication, master node waits for the >> confirmation that a given transaction has committed on slave side >> before committing itself. This wait period can cause some delay, hence >> it is preferable to use sync replication with nodes that far from each >> other. > > I am sure that you wanted to say > "with nodes *not* that far from each other". Oops sorry for the typo. Yes I meant of course "not that far". -- Michael -- Sent via pgsql-general mailing list (pgsql-general@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-general