Return-Path: Delivered-To: apmail-couchdb-dev-archive@www.apache.org Received: (qmail 36877 invoked from network); 8 Feb 2009 08:00:24 -0000 Received: from hermes.apache.org (HELO mail.apache.org) (140.211.11.2) by minotaur.apache.org with SMTP; 8 Feb 2009 08:00:24 -0000 Received: (qmail 61708 invoked by uid 500); 8 Feb 2009 08:00:24 -0000 Delivered-To: apmail-couchdb-dev-archive@couchdb.apache.org Received: (qmail 61669 invoked by uid 500); 8 Feb 2009 08:00:24 -0000 Mailing-List: contact dev-help@couchdb.apache.org; run by ezmlm Precedence: bulk List-Help: List-Unsubscribe: List-Post: List-Id: Reply-To: dev@couchdb.apache.org Delivered-To: mailing list dev@couchdb.apache.org Received: (qmail 61658 invoked by uid 99); 8 Feb 2009 08:00:24 -0000 Received: from nike.apache.org (HELO nike.apache.org) (192.87.106.230) by apache.org (qpsmtpd/0.29) with ESMTP; Sun, 08 Feb 2009 00:00:24 -0800 X-ASF-Spam-Status: No, hits=-0.0 required=10.0 tests=SPF_PASS X-Spam-Check-By: apache.org Received-SPF: pass (nike.apache.org: domain of jchris@gmail.com designates 209.85.221.21 as permitted sender) Received: from [209.85.221.21] (HELO mail-qy0-f21.google.com) (209.85.221.21) by apache.org (qpsmtpd/0.29) with ESMTP; Sun, 08 Feb 2009 08:00:14 +0000 Received: by qyk14 with SMTP id 14so2058492qyk.11 for ; Sat, 07 Feb 2009 23:59:54 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=gamma; h=domainkey-signature:mime-version:sender:received:in-reply-to :references:date:x-google-sender-auth:message-id:subject:from:to :content-type:content-transfer-encoding; bh=5P2ZEbugZX04uIl+kd3QFlk1Fr8sDYhTbkk+Hrg1J7Q=; b=g4HcBvXN/8RcvbqP1uYKelIgchVxmmbw0gl1lFGlWD85Ve1iQb0S+xlVwyy3LCCrfA Uig9Tmd/4C8rj2B0udNn508nNPNeBoM1vjb5b5fUcn8LnhJIzT3AofvLnHMLNSYPrTjs NkZkbKcweNcaKY+5LlMbX/ZChvR7wqTv7BG0E= DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=mime-version:sender:in-reply-to:references:date :x-google-sender-auth:message-id:subject:from:to:content-type :content-transfer-encoding; b=JeDNDV6gnaS3gmSUwEa9/c0MGJhZLOyObAoFZ7KZb0hLfCk0ZRqcfToHdx5BP2GgLj C1RlNg3AJWWjwXax5X5peKBj3I6uTq1PP58EpbziZu0D17CqvrjR33oxbzzC3KHp/Yb9 Vr//QUPpxR2MboYgck8wJ8tQpnGMQ5Zkvyfpk= MIME-Version: 1.0 Sender: jchris@gmail.com Received: by 10.214.25.9 with SMTP id 9mr5003304qay.41.1234079993938; Sat, 07 Feb 2009 23:59:53 -0800 (PST) In-Reply-To: <2157B33F-27F9-44EF-9193-30FCC2926DEB@gmail.com> References: <84F66023-030A-4669-B75C-3DCC92D71A78@yahoo.com> <13619B4B-F8F3-42F6-A18F-0ED07AFDE2D3@gmail.com> <451872B8-152C-42A6-9324-DD52534D9A32@apache.org> <987B2FFD-964D-4DD8-AC8C-C9B6060D64E5@gmail.com> <9540546C-6319-4FA6-8518-E522B62FAE2B@apache.org> <1A6D2CD6-26BC-4C8A-ACC1-EAA5D08E26FB@gmail.com> <178DE634-36CB-40AB-8C6B-7D693E7A7B1B@apache.org> <2157B33F-27F9-44EF-9193-30FCC2926DEB@gmail.com> Date: Sat, 7 Feb 2009 23:59:53 -0800 X-Google-Sender-Auth: 97849800d0c9aa5f Message-ID: Subject: Re: couchdb transactions changes From: Chris Anderson To: dev@couchdb.apache.org Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit X-Virus-Checked: Checked by ClamAV on apache.org I. Replication is concurrent with normal operation, and may or may not be under user control. Normal operation sees conflicts. +1 for handling I correctly. On Sat, Feb 7, 2009 at 10:49 PM, Antony Blakey wrote: > > On 08/02/2009, at 5:05 PM, Damien Katz wrote: > >> In this case it has nothing to do with update transactions. MVCC is about >> each read operation having it's own snapshot of the database. > > Sure, but the MVCC snapshots are created by update transactions, yes? > >> I'm stating that you must "read lock" the source database if you want this >> "consistent replication" thing you are trying to achieve. That's a fact. > > Sorry, I'm just trying to understand how replication, which sees an MVCC > snapshot, requires that I read-lock the source database. > > Antony Blakey > -------------------------- > CTO, Linkuistics Pty Ltd > Ph: 0438 840 787 > > Success is not the key to happiness. Happiness is the key to success. > -- Albert Schweitzer > > -- Chris Anderson http://jchris.mfdz.com