High memory usage on host with a single guest

[Tom Wolf_3]

Hello all.

We have an HP-UX 11.31 ia64 host with a single VM guest.

System memory usage on the host is very high - about 95% of the 40 GB installed in the server.

Even when the guest isn't running system memory usage is at or aboive 95%.

The guest is only configured to use 2 GB of memory.

I check memory usage of running processes and cannot account for what is using all this memory.

I'm very new to virtualization on HP-UX so I'm certain something VM related is allocating this memory but I can't identify it.

Does anyone have any suggestions?

Any assistance would be greatly appreciated.

Thanks in advance.

Tom

[Stan_M]

See HPVM Admin manual - look for HPVM Memory Pool (or 'man hpvmhwmgmt').

In short - HPVM preallocates most of the physical memory to HPVM memory memory to make it reserved for HPVM guests/vPars memory needs at host/VSP boot time.

HTH

Stan

[Tom Wolf_3]

Hello Stan.

Thanks for the response.

Below is the memory pool listing on our host.

According to the man page for hpvmhwmgmt "...The memory pool can be displayed, but not modified."

How would we adjust the amount of memory the virtualization service platform (VSP) grabs at start up.

The man page and guides I looked at aren't real clear about that.

Any additional guidance would be helpful.

Thanks.

# hpvmhwmgmt -p memory -l
System Memory Sizes
  LDOM#    Size(MB)   Free(MB)
     0       40855        913
Total:       40855        913
vPar/VM Memory Pool Sizes
  LDOM#    Size(MB)   Free(MB)
     0       35584      35584
Total:       35584      35584

[Stan_M]

Well, the short answer is - you don't.

Why would you want to change it? The VSP should be dedicated to HPVM hosting and should not be doing anything else. The memory taken apart for HPVM use is the maximum memory deemed safe enough to keep VSP fine while allowing for as much memory in the pool as possible.

The longer answer is - the memory percentage left for VSP can be tuned by tunable HPVM_MEMORY_OVERHEAD_PERCENT  in /etc/rc.config.d/hpvmconf.

It is listed in HPVM admin guide and the same guide advises against tuning it, unless being instructed to do so.

HTH

Stan