vsz field in collect output

[Harmanjit_1]

Hi,

What does VSZ indicate, as when I am checking VSZ with my total swap and physical memory, its crossing 300GB where as my both memory total is 50GB.

Scenario
========
When we convert collect output in text format for reading via collect -p host-collect.cgz > abc.txt.

On opening abc.txt we will get following fields :-

PID User %CPU RSS VSZ UsrTim SysTim IBk OBk Maj Min Command

What is the meaning of VSZ in this field and how it can be more than installed memory+swap.

Thanks

[Venkatesh BL]

VSZ is the 'virtual memory' used by the process. See the manpage of collect for more info.

[Harmanjit_1]

But how virtual memory is exceeding than my total physical+swap memory. My system has total 50GB memory then how come it reach to 300GB used by all processes.

[Venkatesh BL]

I don't think virtual memory is limited by RAM+SWAP size (atleast in theory)...

I think the system swap is configured in 'Lazy' mode so that the kernel doesn't allocate swap space for the process *unless* it is required.

If it was set to 'Eager' mode, you would have seen the system warn about the lack of swap space.

[Mulgund]

You seem to have a large physical memory on your system (in GBs).
Your per process data size can be as large as max per proc data size. Pl. chk per_proc_data_size and max_per_proc_data_size using "sysconfig -q proc" as root on your system.

On my m/c max data size is 1GB.

If my understanding is right VSZ for a process is <= per_proc_data_size.

[Harmanjit_1]

Thanks for your replies. Yes swap is configured in Lazy mode.

Is there is any why with which I can find out which process is taking how much swap at particular time from collect output or anyother Tru64 utility.

[Venkatesh BL]

I am not aware of any tool that gives the per process usage of SWAP.

You can find the system-wide consumption using 'vmstat -R'. 'pout' column gives the number of pages that have been paged out.

[Harmanjit_1]

Thanks for your kind replies.

Regards

[Venkatesh BL]

As I look into ps manpage, I see that '-O nswap' may be used to see the number of swaps done by a process. You may want to check that out.

Also, look into: http://forums1.itrc.hp.com/service/forums/helptips.do?#28

[Harmanjit_1]

Hi,

Hope now, you must have got points. I allocated earlier but may be skipped to submit.

anyhow, thanks