From: Austin Clements Date: Wed, 7 May 2014 17:18:36 +0000 (+2000) Subject: Re: Linux-only fdatasync() in 3c13bc X-Git-Url: http://git.tremily.us/?a=commitdiff_plain;h=b2ce05f36b02e580d97cd98135c61b2d81d45d04;p=notmuch-archives.git Re: Linux-only fdatasync() in 3c13bc --- diff --git a/4f/1e60b6b098ea7241636b08ddb2f428725cf23d b/4f/1e60b6b098ea7241636b08ddb2f428725cf23d new file mode 100644 index 000000000..d394254b5 --- /dev/null +++ b/4f/1e60b6b098ea7241636b08ddb2f428725cf23d @@ -0,0 +1,108 @@ +Return-Path: +X-Original-To: notmuch@notmuchmail.org +Delivered-To: notmuch@notmuchmail.org +Received: from localhost (localhost [127.0.0.1]) + by olra.theworths.org (Postfix) with ESMTP id 25B72431FAF + for ; Wed, 7 May 2014 10:18:52 -0700 (PDT) +X-Virus-Scanned: Debian amavisd-new at olra.theworths.org +X-Spam-Flag: NO +X-Spam-Score: -0.7 +X-Spam-Level: +X-Spam-Status: No, score=-0.7 tagged_above=-999 required=5 + tests=[RCVD_IN_DNSWL_LOW=-0.7] autolearn=disabled +Received: from olra.theworths.org ([127.0.0.1]) + by localhost (olra.theworths.org [127.0.0.1]) (amavisd-new, port 10024) + with ESMTP id xv-i6EeS37kj for ; + Wed, 7 May 2014 10:18:44 -0700 (PDT) +Received: from dmz-mailsec-scanner-6.mit.edu (dmz-mailsec-scanner-6.mit.edu + [18.7.68.35]) + (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) + (No client certificate requested) + by olra.theworths.org (Postfix) with ESMTPS id 64C88431FAE + for ; Wed, 7 May 2014 10:18:44 -0700 (PDT) +X-AuditID: 12074423-f79916d000000c54-3d-536a6af36e1e +Received: from mailhub-auth-3.mit.edu ( [18.9.21.43]) + (using TLS with cipher AES256-SHA (256/256 bits)) + (Client did not present a certificate) + by dmz-mailsec-scanner-6.mit.edu (Symantec Messaging Gateway) with SMTP + id 6E.B1.03156.3FA6A635; Wed, 7 May 2014 13:18:43 -0400 (EDT) +Received: from outgoing.mit.edu (outgoing-auth-1.mit.edu [18.9.28.11]) + by mailhub-auth-3.mit.edu (8.13.8/8.9.2) with ESMTP id s47HIevp000544; + Wed, 7 May 2014 13:18:41 -0400 +Received: from awakening.csail.mit.edu (awakening.csail.mit.edu [18.26.4.91]) + (authenticated bits=0) + (User authenticated as amdragon@ATHENA.MIT.EDU) + by outgoing.mit.edu (8.13.8/8.12.4) with ESMTP id s47HIbe3000314 + (version=TLSv1/SSLv3 cipher=DHE-RSA-AES128-SHA bits=128 verify=NOT); + Wed, 7 May 2014 13:18:39 -0400 +Received: from amthrax by awakening.csail.mit.edu with local (Exim 4.80) + (envelope-from ) + id 1Wi5UL-0004by-BO; Wed, 07 May 2014 13:18:37 -0400 +Date: Wed, 7 May 2014 13:18:36 -0400 +From: Austin Clements +To: David Bremner +Subject: Re: Linux-only fdatasync() in 3c13bc +Message-ID: <20140507171835.GA27619@mit.edu> +References: <20140506195938.GA18213@coyotlan.Tlalpan> + <536a1723.0578e00a.601a.ffff976f@mx.google.com> + + <87vbthu3qx.fsf@maritornes.cs.unb.ca> +MIME-Version: 1.0 +Content-Type: text/plain; charset=utf-8 +Content-Disposition: inline +Content-Transfer-Encoding: 8bit +In-Reply-To: <87vbthu3qx.fsf@maritornes.cs.unb.ca> +User-Agent: Mutt/1.5.21 (2010-09-15) +X-Brightmail-Tracker: + H4sIAAAAAAAAA+NgFtrEKsWRmVeSWpSXmKPExsUixCmqrfs5KyvYYPFhaYsbrd2MFitm9rFZ + XL85k9nizcp5rA4sHjtn3WX3OPx1IYvHs1W3mD22HHrPHMASxWWTkpqTWZZapG+XwJWx+fZ8 + loI9bBVLf05jbGCcydrFyMkhIWAisX/FRHYIW0ziwr31bF2MXBxCArOZJB7f+8kM4WxglNh+ + 8g4LhHOKSeLy6/2MEM4SRomGTbuZQPpZBFQkvv3dzQhiswloSGzbvxzMFhFQlbi6bTLYXGaB + JkaJ3cc3MoMkhAV0JV6v6QVr5hXQkdi15QrU1K2MEj8PfGaHSAhKnJz5hAXEZhZQl/gz7xJQ + MweQLS2x/B8HRFheonnrbLCZnAJGElv+HAYrFwU6aMrJbWwTGIVnIZk0C8mkWQiTZiGZtICR + ZRWjbEpulW5uYmZOcWqybnFyYl5eapGumV5uZoleakrpJkZQ1LC7KO9g/HNQ6RCjAAejEg9v + hnNWsBBrYllxZe4hRkkOJiVR3mnJQCG+pPyUyozE4oz4otKc1OJDjBIczEoivG4ZQDnelMTK + qtSifJiUNAeLkjjvW2urYCGB9MSS1OzU1ILUIpisDAeHkgTv4UygRsGi1PTUirTMnBKENBMH + J8hwHpDhIDW8xQWJucWZ6RD5U4yKUkCjQbYKgCQySvPgemFJ7RWjONArwrwLQKp4gAkRrvsV + 0GAmoMFcxukgg0sSEVJSDYxnlJsqWX6JuZwMTYie/H2C/81HzHYGjLPPit1hC+U6JrB3ndSP + cCWZmxZ2uzj3+po/PX3hidepeCOuf+Jvy/Le+FgaM0/XFo/lKCjYNN3uu8WcBd4Vx/bJNV88 + Pt19ueTXjhSb4t3e2evFrN5pnTlevO59UdXBg/oyLx/v25x8Pyet4Jd88l4lluKMREMt5qLi + RAA+mSVdRQMAAA== +Cc: Tomi Ollila , notmuch@notmuchmail.org +X-BeenThere: notmuch@notmuchmail.org +X-Mailman-Version: 2.1.13 +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: Wed, 07 May 2014 17:18:52 -0000 + +Quoth David Bremner on May 07 at 10:17 pm: +> Tomi Ollila writes: +> +> > On Wed, May 07 2014, Kushal Kumaran wrote: +> > +> >> Xīcò writes: +> >> +> >>> Also, commit 3c13bc introduced a call to fdatasync() which is not +> >>> available on FreeBSD, and probably not either on MacOS at least. +> >>> +> >> +> >> fdatasync is POSIX: +> >> http://pubs.opengroup.org/onlinepubs/009695399/functions/fdatasync.html +> > +> > No wonder it is problematic, then >;) +> > +> +> I seem to recall Austin saying on IRC that this usage was guaranteed to +> call fsync anyway. Comments Austin? + +Yes, since the size of the file will have definitely changed, the +metadata will have to be flushed anyway, so using fdatasync here has +no advantage over using fsync.