You can probably tell I’ve been doing a lot of work with Citrix User Profile Management recently 🙂
One of the problems I faced in my current deployment is that the users I am dealing with are a very particular use case, and as such they very rarely log off. As you probably know, by default UPM only synchronizes your profile changes at logon and logoff. So if you have users that rarely, if ever, log out, to get their UPM profiles properly replicated you have to enable the UPM settings for Active Write Back and Active Write Back Registry. This means that changes they make to their profile will be replicated back to the UPM store (and any configured secondary stores) every five minutes (plus or minus a random offset). You can see this write-back in realtime if you wish to – round about every five minutes any changed filesystem entries and/or Registry hive files will be written to all your configured stores.
Obviously, one of these settings deals with the filesystem and the other with Registry entries. Active Write Back has been around for a long time (since UPM version 3.0).
However, the drawback is that in very busy environments, Active Write Back can cause a lot of strain on the file server and/or storage. I’ve heard tales of very chatty applications that write regularly having a really bad effect on the UPM shared storage. Combine this with logon storms, and you can see where it might become even more detrimental. Go a bit further and factor in multiple secondary stores for replication, and you’re hammering several file shares potentially across different datacenters or hosted environments.
Of course, in this situation you could switch to using UPM Containers instead, but containers aren’t suitable for every environment, and this one was one of those that couldn’t really justify it (although that may change if I can get the local cache functionality working). However, we did think that it would be a good idea to maybe run the Active Write Back synchronization when the user wasn’t busy – such as, when they lock their session, maybe? – and suggested as much to Citrix.
So imagine how cool it was when I noticed in the 2303 release there was now this setting “Active write back on session lock or disconnection”
The setting does exactly what it says on the tin – instead of synchronizing when the session is active, this setting changes Active Write Back and/or Active Write Back Registry (which obviously must be configured for this setting to work) so that their synchronization only starts when the user session enters a locked or disconnected state.
Once configured, you can observe that the changes you make won’t be synchronized to your file stores unless you actually lock or disconnect the session.