Jump to content
Welcome to our new Citrix community!
  • 0

ELM performance


5 answers to this question

Recommended Posts

  • 0

Not that I can do anything about it, but it's worth paying attention to where the time is going.  Creating the VHD inside the elm versus uploading it, and in the case of vSphere, versus the conversion process we have to go through as well (sparse, which is what we know how to make, versus flat, which is what a VM can use).  If you watch the task details, I'd be curious to know where the time is going.


The process of building the VHD in the ELM is mostly bound by IO performance for the ELM VM itself, especially latency.  Our work is generally single-threaded with small I/Os, which magnify any latency effects.  If you're spending hours constructing the disk, focus on the ELM storage. 


The process of uploading could depend on all sorts of things - local storage, destination storage, network path, even (I heard recently) somehow the CPU power of the ELM can impact throughput.  We generally don't recommend extra CPUs on the ELM, but it can't hurt to throw another 4 at it and see if your upload throughput magically increases.


There's a file in the ELM which is at least a little enlightening: /var/log/Unidesk/camjobperf.csv is updated with the duration of each phase of the VHD creation process.  So for istance, I can look at a Publish to PVS I did last week and see the job called ExportImageJob, and the step called CompositeLayersJobStep (which is "copying the layers into the image) took me 1688 seconds.  RegistryAssembly took me 31 seconds, DeployImageToPlatformDeployJobStep took me 310 seconds, and the entire job took 2108 seconds.  OK, probably not a good example, because now that I check that job in my Completed Tasks list, it failed because I was out of space in PVS.  But you get the idea.  No, I don't have a guide for how to read that, and most of what we do takes well less than a second.  But it can help you tease apart the major time consumers of your jobs, and that might help you figure out where to put your resources.

Link to comment

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
  • Create New...