topic Re: New VM Server: Slow Reloads in QlikView

New VM Server: Slow Reloads

matthewjbryant — Wed, 25 Nov 2020 16:16:04 GMT

I just had IT move our QlikView server to a different VM stack, which sits on a box in a different location (the same location as our data sources). Following the move the reload speed has lengthened by about 30%, but IT say the server specifications have been matched.

Pure SQL extracts to QVDs are running about the same, even though they run twice as fast on my local PC when I'm in the office with the new server.

Neither the CPU or RAM are spiking. What should I be looking out for? How can I go about diagnosing the problem?

Re: New VM Server: Slow Reloads

Gysbert_Wassenaar — Wed, 01 Nov 2017 10:30:36 GMT

Network latency and disk i/o?

Re: New VM Server: Slow Reloads

matthewjbryant — Wed, 01 Nov 2017 11:08:18 GMT

Hi Gysbert.

The Disk I/O seems to be all over the place and is spiking, but even when low the tasks are running slowly. Network is also spiking, but not as much.

I've also noticed that running QVWs locally on the server is quicker than the QVS is managing.

Re: New VM Server: Slow Reloads

Or — Wed, 01 Nov 2017 11:17:07 GMT

I'd start by looking at the QVW reload logs - see if the 30% increase is consistent across all of the different sections of your code or specific to some of them by looking at the start/end time for each code chunk / query.

If you can isolate specific things that are slower, that should point you in a direction to look at. If not, your issue is probably related to resources (RAM, I/O, network, etc) or interference (e.g. antivirus).

Keep in mind that running tasks via QVS is always a little bit slower than running them locally in QV.exe - you need to allow for the time to load the file when starting and save the file when finished. Particularly with larger files this can be significant.