A couple of months ago, I reported to this list that we were having login performance issues with Zimbra 6 (in a test environment - we haven't deployed it in production yet). We opened a support case, which stalled, so dug deep into the running JVM to try to figure out what was going on.
It turns out that the issue is caused by mountpoints (shares) - specifically, if userA logs in and has shares from userB and userC's (e.g. their calendars), the login time will depend on how many groups userB and userC belong to. We found that at initial login, it was able to process about 7 groups per second (I won't go into the details of all the ldap lookups that are done). If a mountpoint owner belongs to 150 groups, that adds 20 seconds to login. If userA has a dozen mountpoints, each with dozens of groups, it will take hundreds of seconds to login (which is what we're seeing). And if userB belongs to more than 192 groups, the group lookup goes into an infinite loop and userA can never login.
This seems like an architectural change - as far as I know, Zimbra didn't do any such lookups on mountpoint owners in Zimbra 5 (why is it even necessary to know what groups your mountpoint owners belong to??). As such, it could take awhile to get fixed. We have a support case open on this but haven't heard anything back yet.
If you have Zimbra 6 in test and have users that belong to lots of groups, I'd be curious to hear whether you can reproduce this problem. And of course if you can, I'd hold off upgrading to Zimbra 6!
----- "Hurstel" <hhoward@aurora.edu> wrote:
>
> Hello,
>
> Our window to upgrade to 6 is approaching and was wondering if anyone is experiencing any big problems with 6.0.6?. On the forums I've seen a big thread about GAL lookup slowness. I also see there was an issue with attachments but that has been fixed in the support portal. Any help would be appreciated.
>
> Hurstel
>
>
Hurstel Howard
Systems Administrator
> Aurora University
> 630-844-4889
hhoward@aurora.edu
>
>
--
Steve Hillman IT Architect
hillman@sfu.ca IT Infrastructure
778-782-3960 Simon Fraser University