When we talk about XenApp and XenDesktop implementations and the aspects of profiles, we always hear the recommendation to redirect folders. It is a great way to offload portions of your profile to speed up logons, because those folders are not copied down to the system during logon. In fact, I typically recommend the redirection of Favorites, desktop, downloads and My Documents. But the question is what to do about AppData.
I actually had this discussion at BriForum 2010 with a number of people (well, the following discussion is not word-for-word, but you’ll get the idea). You might be thinking, what’s the big deal? Why is AppData so special that we are even discussing it? Let’s look at it from both perspectives:
By redirecting AppData, we can expect logons to happen much faster because this folder can become quite large. AppData is all dependent on the applications and some applications store large numbers of files or large sized files in the folder. If we don’t have to copy these file down, then we effectively speed up logons.
Well, some applications use AppData constantly. Certain applications will write and read tons of information to that folder. If the folder is not local, then the application performance might degrade. From this perspective, users are in applications for a larger percentage of time than they are logging in so it would be better to improve a greater portion of time.
But by not redirecting the folder, you assume every user will use that application, which is not the case, but I can guarantee that every user using the system has to logon, which means we have a positive impact on everyone. So even though certain users are in the app for a long time, there is a large percentage of users who don’t use the application at all. So in effect, you are hurting their logon times without giving them any benefits.
But application performance is where we end up hearing user complain to the help desk. And honestly, how much of an impact on logon time are we even talking about? An extra 10 seconds? Big deal.
You are wrong
Let’s just blame the networking team and be done with it
In the end you have to pick your poison. Do you want a faster logon time or faster application performance? I typically recommend we redirect AppData. IF we see application performance issues, we can use a solution like Citrix Profile Management to allow certain folders to be copied to the local system. This way, we can get the best of both worlds: fast logon and application performance.
Which side do you take?
Daniel – Lead Architect