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svmon - RAM

Statistics reported by svmon are expressed in terms of pages. A page is a 4K block of virtual memory while a frame is a 4K block of real memory.

These parameters show the number of both the working and persistent pages in RAM.

svmon -G    shows global memory reports (in 4K page sizes)
               size       inuse        free         pin     virtual
memory      4096000     2423149     1672851      803943     1734262
pg space    2097152      103815

               work        pers        clnt       other
pin          665509           0          99      138335
in use      1711933           0      711216

PageSize   PoolSize      inuse       pgsp        pin    virtual
s   4 KB          -    2284685     103815     731591    1595798
m  64 KB          -       8654          0       4522       8654


DETAILS ABOUT RAM:

memory - specifies statistics describing the use of real memory, including:
    size -    number of real memory frames (size of real memory) (in kbytes=4096000 * 4)
    inuse -   pages used by processes + the number of persistent pages that belonged to a terminated process and is still resident in RAM
    free -    number of frames free of all memory pools (free RAM) (amount of pages on the free list in 4k pages)
    pin -     number of frames containing pinned pages (the number of pages pinned in physical memory (RAM). This cannot be paged out)


pin - specifies statistics on the subset of real memory containing pinned pages, including:
    work -    number of frames containing working segment pinned pages
    pers -    number of frames containing persistent segment pinned pages
    clnt -    number of frames containing client segment pinned pages


in use - specifies statistics on the subset of real memory in use, including:
    work -    number of frames containing working segment pages
    pers -    number of frames containing persistent segment pages
    clnt -    mumber of frames containing client segment pages

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DETAILS ABOUT PAGING SPACE:


pg space - specifies statistics describing the use of paging space.
    size -    size of paging space
    inuse -   number of paging space pages used

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DETAILS ABOUT 4KB 64KB 16MB PAGES:
    PageSize -the size of the pages considered.
    Inuse -   indicates the total number of pages of PageSize in real memory in segments that are used by the user.
    Pin -     indicates the total number of pages of PageSize pinned in segments that are used by the user.
    Pgsp -    indicates the total number of pages of PageSize reserved or used on paging space by segments that are used by the user.
 
       The different values are expressed in the PageSize pages unit.


In the below case 885*16MB is reserved but nothing is using it (inuse=0)
    PageSize   PoolSize      inuse       pgsp        pin    virtual
    s   4 KB          -    4289065       9348     804589    3562062
    m  64 KB          -      10536          0       8102      10536
    L  16 MB        885          0          0        885          0
   

This could be checked with vmo as well:   
vmo -a|egrep "lgpg_regions|lgpg_size"
    lgpg_regions = 885
    lgpg_size = 16777216    <-16MB

IBM recommendation was to turn this off:
vmo -r -o lgpg_size=0 -o lgpg_regions=0     <--we did a reboot after that

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svmon -P 278620
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     Pid Command          Inuse      Pin     Pgsp  Virtual 64-bit Mthrd LPage
  278620 shm_lgpg64       13781    11319     1083    13769      Y     N     Y
     PageSize      Inuse        Pin       Pgsp    Virtual
         4 KB       5589       3127       1083       5577
        16 MB          2          2          0          2

This process uses 13781 pages in real memory. 11319 frames are pinned.
The number of pages reserved or used in paging space is 1083.

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     Pid Command          Inuse      Pin     Pgsp  Virtual 64-bit Mthrd  16MB
 2781436 oracle        14086839    65566  1784541 14122372      Y     N     N

16MB N: it means this process does not use the 16MB pages, N=no

8 comments:

  1. Hi,
    use the below command to find the top 15 process with details.

    svmon -Pt15 | perl -e 'while(<>){print if($.==2||$&&&!$s++);$.=0 if(/^-+$/)}'

    ReplyDelete
    Replies
    1. Hi, thanks for this really nice command :-)

      Delete
  2. apart from above command you can use svmon -P -O unit=MB|head -15(it will also display same thing in MB)

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  3. This comment has been removed by the author.

    ReplyDelete
  4. How i can get overall memory and CPU utilization in percentage ?

    ReplyDelete
  5. I'm trying in AIX box..
    For memory using = svmon -G -O unit=GB
    For cpu using = sar -u 5 5
    using script how i can get the value in percentage and schedule as a job

    ReplyDelete
  6. how can you manage high paging size, meaning using command #ipcrm ? I've done a research on the net, and saw people uning it with success for processes with NATTCH equal zero. What's your opinion on that?

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