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PageSize Inuse Pin Pgsp Virtual

4KB 448221 3687 2675 449797

16MB 0 0 0 0

Vsid Esid Type Description LPage Inuse Pin Pgsp Virtual

1f187f 11 work text data BSS heap - 56789 0 0 56789

218a2 70000000 work default shmat/mmap - 33680 0 0 33680

131893 17 work text data BSS heap - 21840 324 0 21840

0 0 work kernel segment - 4902 3327 2563 6419

1118b1 8001000a work private load - 1405 0 0 1405

d09ad 90000000 work loader segment - 1039 0 42 1226

1611b6 90020014 work shared library text - 169 0 65 194

31823 10 clnt text data BSS heap - 145 0 - -

1a187a ffffffff work application stack - 50 0 0 50

c17ec f00000002 work process private - 31 22 0 31

b11ab 9fffffff pers shared library text, - 10 0 - -

3.3.2 vmstat

The vmstat command can show how many large pages are available for an application. It also

reports paging activity, which can indicate if thrashing is taking place. It can also be used to find

the memory footprint of an application. Unlike svmon, it does not require you to run as root.

To see a one-line summary of the vmstat statistics, enter the following command:

vmstat -l

The first part of the output reports the number of CPUs and the amount of usable physical

memory.

System Configuration: lcpu=32 mem=157696MB

kthr memory page faults cpu large-page

----- --------------------- ---------------------------- ------------------ ------------------ ------------

r b avm fre re pi po fr sr cy in sy cs us sy id wa alp flp

3 1 35953577 5188383 0 0 0 0 0 0 3334 2080 176 1 0 99 0 213 7787

The output is grouped into five categories. The last one, the large-page group, has two members:

allocated large pages (alp) and free large pages (flp). Because large pages are mapped into the

process address space in 256MB segments, the maximum number of segments an application can

get is flp * 16 / 256 . alp. This includes HPS buffers allocated in support of MPI processes on

the adapters and buffers for IP. If only one application is running on a node or LPAR, the

memory footprint of the application is the number of Active Virtual Memory (avm) pages. This

can also be measured as the difference in avm before the application was started and when it is

running. The avm is given in 4K units.

The vmstat command allows sampling at fixed intervals of time. This is done by adding an

interval in seconds to the vmstat command. For example, the following command shows vmstat

IBM pSeries User Manual Page 12