Memory Utilisation

[SSP_1]

Hi Experts,

I am running glance and confused about the output of memory util . Could you pl explain me all the terms which are mentioned below and which glance report shows.


Total VM : 8.45gb Sys Mem : 739.4mb User Mem: 2.81gb Phys Mem: 3.99gb
Active VM: 6.47gb Buf Cache: 409.5mb Free Mem: 62.5mb

[Dietmar Konermann · Accepted solution]

You should have a look at the online help of Glance. Most metrics are pretty well documented there. From the memory report screen press "h" and then select "Current Screen Metrics".

Best regards...
Dietmar.

[Michael Steele_2]

From p. 546 - Total VM:

virtual memory
Secondary memory that exists on a portion of a disk or other storage
device. It is used as an extension of the primary physical memory.

Basically its swap, more specifically its the paging mechanism.

Sys Mem: System memory.
User Mem: User memory.
Phys Mem: Physical Memory.

Active Mem: There are active processes using memory and sleeping processes.

Buf Cache: An area of memory that mediates between application programs and
disk drives. When a program writes data, it is first placed in the buffer
cache, then delivered to the disk at a later time. This allows the disk
driver to perform IO operations in batches, minimizing seek time.

free mem:
Memory not currently allocated to any user process or to the kernel.


This was a good document:

http://www.usg.edu/OIIT/support/os/HP-UX_10.20/white_memman.html

I didn't like this document as much:

http://docs.hp.com/hpux/pdf/B3691-90061.pdf

[Uday_S_Ankolekar]

Shripad,

Online help is the best way and also have a look at the following doc ( a pdf file)

/opt/perf/paperdocs/gp/C/concepts.pdf



-USA..