| Re: Limit to used pages not allocated ones [message #16404 is a reply to message #16403] |
Wed, 05 September 2007 03:07  |
Vasily Tarasov
Messages: 1345
Registered: January 2006
|
Senior Member |
|
|
Hi,
you wrote: | Quote: |
Is it possible with OpenVZ to limit the used pages (which is showed in the physpages) and not the allocated (privvmpages) ones?
|
It isn't possible now, 'cause of some peculiarities of Linux memory management. 
you wrote: | Quote: |
What happens if I set the oomguarpages to 256M limit and set privvmpages to unlimited?
|
If you do so, OOM condition will be more probable (look at http://wiki.openvz.org/Oomguarpages#oomguarpages page). If it is OK for your customers, then, I think, you can do it. At least, look at the table http://wiki.openvz.org/UBC_configuration_examples - they do it in some examples 
you wrote: | Quote: |
I saw that the oomguarpages and physpages always shows the same value. Is it real? Or if the OOM occurs this can be different?
|
physpages parameter accounts only used RAM, while oomguarpages parameter accounts RAM+SWAP. So, if you force some VE to use SWAP - this values will be different.
you wrote: | Quote: |
I think the allocated but unused memory means that the memory not really allocated from the physical memory. Am I right?
|
Yes, you're right.
you wrote: | Quote: |
The root of the problem is that lot of our customers runs programs which has very big difference between the privvmpages and the physpages value. They complaining all the time about this problem.
|
Yeap, this is a commons problem. I think the table http://wiki.openvz.org/UBC_configuration_examples can help you to make right desicion. 
HTH,
Vasily
|
|
|
|
OpenVZ Forum
Members
Search
Help
Register
Login
Home
