R: More Skiplist Stuff!

[David Carter]

On Tue, 15 Jan 2008, Toschi Pietro wrote:

> I'm afraid to bother on the devel list since I'm not a developer, but 
> I've got some confusion about what patches should I apply to a fresh 
> 2.3.11 cyrus-imapd tarball in order to have a not-broken skiplist 
> mailboxes.db (and possibly all the remaining backends too) and avoid 
> those problematic DB ERRORS and reconstruct? Would you be so kind and 
> please summarize and put some light about the correct patching-path that 
> we (simply humans) should follow (possibly before your escape to the 
> Tasmanian bushes, Bron :-))

I think that you only really need to worry if you are running Fastmail's 
folder_limit patch. The following two cleanups have been merged upstream:

     cyrus-skiplist-safelock-2.3.11.diff
     cyrus-skiplist-state-2.3.11.diff

and should apply either way around.

But this was really just Bron hunting down the root cause of the problem: 
the fact that the folder_limit patch was accidently blowing away the write 
lock on the mailboxes.db skiplist database. This is what the third patch:

   cyrus-skiplist-transactions-2.3.10.diff

works around, by reusing the existing transaction and write lock if a 
mboxlist_count_inferiors() occurs in the middle of a transaction.

-- 
David Carter                             Email: David.Carter at ucs.cam.ac.uk
University Computing Service,            Phone: (01223) 334502
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