On Mon, 28 Jul 2003, Andrew McNamara wrote: > This sounds like the same problem I complained about on the list in > the thread, subject "Very slow deletion of user mailboxes?", posted 9th > July. I haven't had a chance to investigate further. > > http://asg.web.cmu.edu/archive/message.php?mailbox=archive.info-cyrus&msg=23597
I finally took a look at this. I have good and bad news... The good news is that I know what it is. The bad news is that fixing it correctly will be horrendously slow (fixing it incorrectly is already in CVS for 2.1 atleast, which is OK for reasons that will be clear in a moment). The problem is that when you remove a user mailbox, it is necessary to prune the user from all possible existing ACLs. This is a hideously expensive process, that has in fact been stubbed out in the code for some time (the function is user.c:user_deleteacl). Unfortuinately, we still were iterating across the mailbox list calling the stub function. This isn't a good idea (and, with skiplist, involves a lot more syscalls). We definately want to actually do something better here in the future. This probably involves using unique user id numbers or similar. Now, in 2.2 there are two separate problems: one is shared above with 2.1. The other is the question of user renames. When a user is renamed, it *is* necessary to actually go through and update all the ACLs live, otherwise that user isn't actually renamed (they lose access to folders they should have access to, since we don't have unique id #s). However, in Scott's case, he's not renaming the user, he's just moving it between partitions. I don't think we should be iterating across the list to fix the username in this case (so we should fix this ;)... -Rob -=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=- Rob Siemborski * Andrew Systems Group * Cyert Hall 207 * 412-268-7456 Research Systems Programmer * /usr/contributed Gatekeeper
