From: Daniel Schoepe Date: Mon, 10 Aug 2015 09:40:21 +0000 (+0200) Subject: Re: [PATCH 4/5] cli: add global option "--uuid" X-Git-Url: http://git.tremily.us/?a=commitdiff_plain;h=6ea88c37186ea4420724c54162e7c5e60a58cc28;p=notmuch-archives.git Re: [PATCH 4/5] cli: add global option "--uuid" --- diff --git a/ce/0361e9945e5c080be7747597ac1027bd50abca b/ce/0361e9945e5c080be7747597ac1027bd50abca new file mode 100644 index 000000000..42345d946 --- /dev/null +++ b/ce/0361e9945e5c080be7747597ac1027bd50abca @@ -0,0 +1,103 @@ +Return-Path: +X-Original-To: notmuch@notmuchmail.org +Delivered-To: notmuch@notmuchmail.org +Received: from localhost (localhost [127.0.0.1]) + by arlo.cworth.org (Postfix) with ESMTP id 3D3C56DE099D + for ; Mon, 10 Aug 2015 02:40:31 -0700 (PDT) +X-Virus-Scanned: Debian amavisd-new at cworth.org +X-Spam-Flag: NO +X-Spam-Score: -0.11 +X-Spam-Level: +X-Spam-Status: No, score=-0.11 tagged_above=-999 required=5 tests=[AWL=0.097, + DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, + RCVD_IN_DNSWL_LOW=-0.7, RCVD_IN_MSPIKE_H3=-0.01, + RCVD_IN_MSPIKE_WL=-0.01, RCVD_IN_SORBS_WEB=0.614, SPF_PASS=-0.001] + autolearn=disabled +Received: from arlo.cworth.org ([127.0.0.1]) + by localhost (arlo.cworth.org [127.0.0.1]) (amavisd-new, port 10024) + with ESMTP id 9puF84tGk56y for ; + Mon, 10 Aug 2015 02:40:29 -0700 (PDT) +Received: from mail-wi0-f177.google.com (mail-wi0-f177.google.com + [209.85.212.177]) + by arlo.cworth.org (Postfix) with ESMTPS id F07C36DE0244 + for ; Mon, 10 Aug 2015 02:40:28 -0700 (PDT) +Received: by wijp15 with SMTP id p15so128138393wij.0 + for ; Mon, 10 Aug 2015 02:40:26 -0700 (PDT) +DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=schoepe.org; s=google; + h=from:to:subject:in-reply-to:references:user-agent:date:message-id + :mime-version:content-type; + bh=NM5vOvefEmGvwLmbUPmyv4Lt4vIzRMETzJBnV9Ep0kY=; + b=NMerkH3ZruGDymV75CUqw4AtKTDxqvv8x1NEXz0VoUB/R6Cw7Y7OB1p6o8Fjqu2u4H + FYq/ykeoA+cBGUklYyakWvsbJ3CITAYm+asJg7ziAVLWBzRnYlfQWEVqUgSXSeiXy6bP + bFlhVjkvXc8jYIajpTMWOAE1F/JhcrmawC3QE= +X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; + d=1e100.net; s=20130820; + h=x-gm-message-state:from:to:subject:in-reply-to:references + :user-agent:date:message-id:mime-version:content-type; + bh=NM5vOvefEmGvwLmbUPmyv4Lt4vIzRMETzJBnV9Ep0kY=; + b=cLEk5UbBfYnJPHRoe7uewu9W2ap03Fvyz73HuCaCMAJdKnmeY4nGPAs7QYj81g6OVZ + M2+dWuaeJcAihSO1//qR1D7HmaZwkpA0vnxW3zhuP00pdkwuXrzmG6FblgeLds+7+WSy + dkNvre1vMeo5hlOMJyrGC2hoWH6GYWWuDbmudWF7W/rGgD3t5O/dV6bmawsbD84XZpX7 + MXhyFe/b9evLBMD7EqIedCuUMyBczSCf4WWuj6Lw7r3bAumFeSk9WAEJEFeMdWeoTyRo + HfPUGxrNImsGazCMyCXy/hjfYBKWsh+hgg8U2C7ZweGZ3BdIdJ9l34v5Zk4AqERsB/X5 + 1njw== +X-Gm-Message-State: + ALoCoQlpHEhqeV3uUrvJep6/MvbEHfKSrAFvuAz9/UFxyXXg9wSiuAqQB/gki4UDHsX+TnjF9jbv +X-Received: by 10.194.172.130 with SMTP id bc2mr46488639wjc.85.1439199626796; + Mon, 10 Aug 2015 02:40:26 -0700 (PDT) +Received: from localhost (ip-80-226-24-8.vodafone-net.de. [80.226.24.8]) + by smtp.gmail.com with ESMTPSA id fs8sm1649964wib.0.2015.08.10.02.40.24 + (version=TLSv1.2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); + Mon, 10 Aug 2015 02:40:25 -0700 (PDT) +From: Daniel Schoepe +To: David Bremner , notmuch@notmuchmail.org +Subject: Re: [PATCH 4/5] cli: add global option "--uuid" +In-Reply-To: <1439112285-6681-5-git-send-email-david@tethera.net> +References: <1439112285-6681-1-git-send-email-david@tethera.net> + <1439112285-6681-5-git-send-email-david@tethera.net> +User-Agent: Notmuch/0.20.2+58~g20ed908 (http://notmuchmail.org) Emacs/24.5.1 + (x86_64-unknown-linux-gnu) +Date: Mon, 10 Aug 2015 11:40:21 +0200 +Message-ID: <87fv3rtray.fsf@schoepe.localhost> +MIME-Version: 1.0 +Content-Type: text/plain +X-BeenThere: notmuch@notmuchmail.org +X-Mailman-Version: 2.1.18 +Precedence: list +List-Id: "Use and development of the notmuch mail system." + +List-Unsubscribe: , + +List-Archive: +List-Post: +List-Help: +List-Subscribe: , + +X-List-Received-Date: Mon, 10 Aug 2015 09:40:31 -0000 + +On Sun, 09 Aug 2015 11:24+0200, David Bremner wrote: +> + ``--uuid=HEX`` +> + Enforce that the database UUID (a unique identifier which +> + persists until e.g. the database is compacted) +> + is HEX; exit with an error if it is not. This is useful to +> + detect rollover in modification counts on messages. You can +> + find this UUID in the first column of output from +> + ``notmuch count --output=modifications`` + +I think it's not entirely clear what the connection between the UUID and +the revisions on messages is. For example, compacting a database +shouldn't make a difference "extensionally", so the naive assumption +might be that the UUID, or, maybe more importantly, the revision counts +don't change. + +For example, if lastmod queries are used to incrementally back up or +synchronize tags, then it doesn't matter if the database got compacted, +all one cares about are the changes to messages' tags since an earlier +point. + +Based on quick experiments, it seems that the revisions don't change +when compacting the database; is this something that the patches +guarantee or a coincidence? + +Best regards, +Daniel