On Tue, 14 Sep 2004, Attila Nagy wrote:
http://www-uxsup.csx.cam.ac.uk/~dpc22/cyrus/replication.htmlThere are some problems with that: - the code isn't available on that webpage
No, but the code is available to people who want to play with it on the understanding that they get no sympathy from me if they try and run it on a production server right now.
- it changes the mailstore layout, so you cut off yourself if you use that instead of the mainstream version
The incompatible change is actually just a single 96 bit value per message in the cyrus index file (a message UUID value, used to replicate the single instance store). If a future UUID format was agreed and space was reserved in current index files, the incompatibility would disappear. That might be a path to more widespread testing.
- I guess it is for an older Cyrus, so you cannot easily upgrade
I passed a patch relative to 2.3 CVS on to Rob a few months back. The replication code is largely orthogonal to the existing code: it only took me a couple of hours to generate the patch from my existing 2.1.16 code.
I cannot say anything about its architectural problems, if there are any at all.
I consider the code to be a prototype of the "obvious" way to do application level replication in Cyrus. It works fine for us, but would clearly require a careful audit before going into more widespread use.
Support for a number of things is missing simply because we have no need for them right now: seen state handling for shared mail folders, quota roots other than user.<whatever>, and in 2.2+ mailbox annotation and virtual domains spring to mind. I don't think that any of these things would be particularly hard to do, its just a Small Matter of Programming.
I would estimate that I've put in about around 3 to 4 months work on the current code and that we would be talking about (at least!) several more man months work between myself and Cyrus developers to get something properly merged. Thats a fairly substantial undertaking for all involved, particularly given that we all have other priorities.
-- David Carter Email: [EMAIL PROTECTED] University Computing Service, Phone: (01223) 334502 New Museums Site, Pembroke Street, Fax: (01223) 334679 Cambridge UK. CB2 3QH. --- Cyrus Home Page: http://asg.web.cmu.edu/cyrus Cyrus Wiki/FAQ: http://cyruswiki.andrew.cmu.edu List Archives/Info: http://asg.web.cmu.edu/cyrus/mailing-list.html
