Troubleshooting problems related to loading and caching speed is tricky because there are just too many factors involved and when you think you have a good overview there is always something which is overlooked.
In this article I want to share my experience around the different issues we have had while going from App-V 4.5 installed on server 2003 to 4.6.1 on server 2008 R2.
So let’s start at the beginning, we had version 4.5 installed and wanted to upgrade to 4.6 as soon as possible. Both clients and management server were running server 2003 at this point. In the beginning we did not have any issues; this was because all of our packages were sequenced with a 4.5 sequencer. But as we created more and more packages with the new 4.6 sequencer we noticed an increase in cache time. This could be an Adobe package weighing in on 700Mb taking 15 minutes from clicking on the shortcut till it opens. At this point we created a support ticket with Microsoft as well as ask the community if someone else had the same problem.(1)
Microsoft were quick to respond and really interested and helpful which we appreciate, so thank you Microsoft. We started looking at our network, which components could interfere and of course driver versions. Long story short, this issue was caused by the change of default block size from version 4.5 to 4.6. As you might know, the default block size was changed from 32KB to 64KB. We used a tool called Application Virtualization Explorer to change the block size back to 32KB just to see if that really make any difference. With positive results, we were excited to have found the cause. Microsoft quickly came up with a solution which involved changing the value of a registry key called EnableTCPChimney. TCP Chimney is a stateful offload. TCP Chimney offload enables TCP/IP processing to be offloaded to network adapters that can handle the TCP/IP processing in hardware.(2) After you install Windows Server 2003 Service Pack 2 or Windows Server 2003 Scalable Networking Pack on a computer that has a TCP/IP Offload-enabled network adapter, you may experience many network-related problems.(3) In other words, extensive testing is a very good idea if you are considering this change. I’m happy to inform we successfully upgraded all our clients to 4.6 with no further issues.
A couple of months later we agreed we had too much uptime and started looking into the possibility of upgrading to Windows Server 2008 R2. This was when Microsoft released App-V 4.6 service pack 1, which left us with a completely new environment really. We quickly sequenced up some apps with the new and awesome 4.6.1 sequencer, just to get started testing. During testing however we noticed that apps kept hanging upon launch and the duration of “checking for updates” was too long. Yet again we opened a ticket at Microsoft. They could not help us with this issue and it was only when I installed a new management server with windows server 2008 R2 the problem went away.
This next issue occurred after we had installed App-V 4.6 SP1 in our Windows Server 2003 environment. We received complaints from users who had issues with apps started from a mapped network drive. This problem occurs with UNC paths as well and only happens on Windows XP and Windows Sever 2003 where the App-V 4.6 SP1 client is installed. Windows 7, Windows Server 2008 / R2 and 4.6 RTM clients are not affected. Microsoft quickly acknowledged the problem(4) and came out with a fix this august(5).
Well, that is all I wanted to share. Below are some links where you can read more about what I have been talking about. I have marked the different events with a number in brackets so it’s easier to see which link belongs to which event.
Thanks for reading.
Related posts and more info about what this article discusses:
1: http://www.appvirtguru.com/viewtopic.php?f=9&t=3598&start=15
2: http://support.microsoft.com/kb/912222
3: http://support.microsoft.com/kb/948496
4: http://blogs.technet.com/b/appv/archive/2011/06/01/app-v-4-6-sp1-issue-running-a-virtualized-app-v-application-that-is-started-from-a-network-location.aspx
5: http://support.microsoft.com/kb/2307495
Edited 09/08/2011