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Re: [Xen-users] Can't Allocate Memory

> None that I know of.  I've run into this issue many times in test,
> with both RHEL and SLES and it's an ongoing problem that no one seems
> to be able to resolve.  The other issue is that this is not
> necessarily easy to reproduce either.
> The oddity here is that you are still seeing the problem.  In every
> case I've run across, limiting dom0 like you've done resolved the
> problem.
> This makes me wonder a few things...
> 1:  how many domUs do you have running, and what are their memory limits?

Total system RAM 14gb.
dom0 = 2gb
server1 (full) = 3gb
server2 (full) = 1gb
server3 (para) = 3gb (NOT running)
server4 (para) = 1gb
server5 (full) = 512meg  (NOT running)
server6 (full) = 512meg
server7 (full) = 1gb  (NOT running)
server8 (full) = 512mg  (NOT running)

full = windows full virt
para = linux para virt

> 2:  Have you tried a full restart, along with limiting the max memory
> for each domU to ensure that the guests don't try grabbing too much
> memory? As I recall, besides limiting dom0's max, if you don't limit
> the domU max they too will be able to grab additional RAM.

Was not aware you could/should limit the domU's. Can you tell me that
setting? I'm willing to try it, but according to virt-manager they are
all using what they are supposed to. 

> 3:  Are you in a scenario where you are starting and stopping them
> repeatedly?  That's more a curiosity for me, as I wonder if you are
> stopping some guests and their memory is not being released to the
> pool for other guests to grab as they are started.

Not really, but their certainly has been a number of stops and

> 4:  Not that it makes THAT much difference, but are you running 32bit
> or 64bit SLES?


> 5:  Finally, again, not that it should make too much difference, but
> if this is a NUMA capable machine, are you enabling NUMA at boot time?
>  I don't know that NUMA would do anything to help or hinder here, but
> it's a thought at least.

Don't know if it's NUMA capable. This machine is an HP DL360-G5. I don't
see any NUMA parameter in the boot parameters.


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