From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: From: Philipp Reisner To: "Graham, Simon" Subject: Re: [Drbd-dev] Handling on-disk caches Date: Mon, 12 Nov 2007 17:24:12 +0100 References: <342BAC0A5467384983B586A6B0B376710707496D@EXNA.corp.stratus.com> <342BAC0A5467384983B586A6B0B3767107074F83@EXNA.corp.stratus.com> In-Reply-To: <342BAC0A5467384983B586A6B0B3767107074F83@EXNA.corp.stratus.com> MIME-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable Content-Disposition: inline Message-Id: <200711121724.12490.philipp.reisner@linbit.com> Cc: drbd-dev@lists.linbit.com List-Id: Coordination of development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , On Monday 12 November 2007 16:59:24 Graham, Simon wrote: > > For item 3 I have an other opinion. > > > > On the primary we have a data structure called the "transfer log" or > > tl > > > in the code. Up to now this was mainly important for protocol A and B. > > > > It is a data structure conaining objects for all our self-generated > > drbd-barriers on the fly, and objects for all write requests between > > these barriers. > > > > If we loose connection in protocol A or B we need to mark everything > > we find in the transfer_log as out-of-sync in the bitmap. > > > > When we also do this for protocol C, _AND_ use BIO_RW_BARRIER for > > doing writing on the secondary we have solved the issue you > > described in the first part of the mail. > > I like it! MUCH better than marking the GB's of data covered by the > AL... > > I presume you will work on this as part of 8.2 rather than as a fix to > 8.0? Since I am currently locked on 8.0, I will probably look at > implementing your suggestions as updates to 8.0 and submit them for > consideration in 8.2. Right, I thought about this, and forgot to mention it in the mail. =46rom a technical point of view it is possible to do the BIO_RW_BARRIER stuff in DRBD-8.0 since it can be done without changing the protocol. =46rom the point of view as release manager I get bellyache when considering such a big change for DRBD-8.0. Please start the work based on the 8.0 tree, I postpone the decision if it should go into 8.2 only or into 8.0 (and propagated to=20 8.2 of course as well) until we see the intrusiveness of the patch. Moving patches between 8.0 and 8.2 is still quite possible...=20 =2DPhil =2D-=20 : Dipl-Ing Philipp Reisner Tel +43-1-8178292-50 : : LINBIT Information Technologies GmbH Fax +43-1-8178292-82 : : Vivenotgasse 48, 1120 Vienna, Austria http://www.linbit.com :