I think it would be safe to say that Shared Cache in App-V 4.6 was not the most popular solution for reducing the impact of App-V cache on client machines. From VDI to RDS, people didn’t want to duplicate the potentially huge sftfs.fsd cache file across their disks and consume unnecessary space. The Share Cache solution was a way around this however it could prove to be hard to manage when trying to update a centrally located cache file to which multiple machines had a handle to.
Enter Shared Content Store with App-V 5.0!
Shared Content Store in App-V 5.0 allows us to stream directly from a content source without having to stream the package to the local platform. The great thing is App-V 5.0 packages now use a flat file format and are no longer stored collectively in a single cache file, which means we no longer have the read only challenges we faced with the Shared Cache solution in App-V 4.6 when it comes to updating applications and replacing the cache.
You will notice the size on disk matches the file size, this package is currently cached locally on this machine.
However if we enable Shared Content Store we can choose not to hold these files locally and instead stream from the content source directly. We can enable this setting during installation by using the following switch for installation: appv_client_setup.exe /SHAREDCONTENTSTOREMODE=1 /q
We can also enable this setting after installation by using PowerShell:
Set-AppvClientConfiguration -SharedContentStoreMode 1
Or we can use this simple registry change on the client as shown:
After a reboot of the client, next time we publish an application, it no longer downloads the entire package but instead creates NTFS pointers to the files which only consume 4KB on disk:
You will notice the change in icons for the App-V WinRar package files also indicating that these are sparse files which actually do not contain the data locally. The package will now utilise the original stream location for these files to run the application without ever having to download them locally to disk. A very small percentage of package files will always have to stay local however such as icons and metadata, this is called the publishing feature block, read more about it here.
So that is a quick overview of Shared Content Store in App-V 5.0, click here for a deeper look into how this great feature works.