Limit QVB.exe processor use?

[#1]

Hi,

Sometimes QVB.exe goes up to 99% CPU use. Is there a way to limit the amount of processor used by it?

[danielrozental]

I've actually discussed this with someone from QT Support and sadly there is none.

Perhaps you can check your reloads to see if they can be done more efficiently.

[StefanBackstrand]

The QVB process will work in the same fashion as Qlikview Desktop and Server (Qv & QVS) - it will use the optimal amount of CPU resources to satisfy the request as fast as possible. Having a Publisher process that uses 100% CPU in intervals is not neccesarily a bad thing, unless the processing times are long and/or distrurbs other processes on the system. In that case you scale out the architecture by layering QVS and Publisher on separate hardware, for example. Trying to create shelves for QVS and Publisher will in the long end only result in a general performance degradation, since statically reserving CPU resources to processes will create scenarios where unused resources at times will not be used at all.

[danielrozental]

It will still be nice to be able to limit how much resources a QVB uses. When you have several tasks running at the same time and they are all spreading into multiple threads trying to grab as much resources as possible it can get a bit messy.

[StefanBackstrand]

Daniel,

Resources in what sense - number of CPU cores? Number of CPU cycles? Priority?

The Windows sub system has logic to context switch resource fights in the OS, to try and balance usage accordingly.

[danielrozental]

Mostly number of CPU Cores, number of threads and memory.

We've had many stability issues in clients that were streching their server resources to the limit, like COM Exceptions, I/O problems, services instability that we were not getting with QV9.

Windows can balance usage but doesn't know what tasks are more important than others or have more dependencies.

[#7]

Try VMWare, run in a VM.

[StefanBackstrand]

Sam; Im sorry, but no, absolutely not. Virtualization is not meant to constrict software within boundaries, but to overcommit and share resources on the hardware layer. That will unfortunately not solve the issue, and will not scale Qlikview accordingly.

Daniel; restricting memory only gets you into the situation where more CPU resources are needed, for example if cache space runs out. CPU usage, and threading, pooling will also create scenarios where resource shortage are even more apparent than without it, in a Qlikview world.

Maybe smarter algorithms when starting services could provide intelligence to decide what resources are needed during a specific task, but were not there yet.

[#9]

...thx Stefan, just an idea we used at a company I was with to stop any one process from pegging an entire server.

[#10]

If you are using 32 bit windows server then I recommend threadmaster which is freeware and very good at what it does. I am having the same issue but now using windows 64 bit which threadmaster does not support so back to the drawing board. Cheers.