Performance issue

[Former Member]

Dears,

I am facing one performance problem in my ECC5 server.My all buffers and extended memory is getting full again and again.

In ST06,

Physical mem avail Kb 8.728.640 Physical mem free Kb 10.692

Free in swap-space Kb 25.678.432

Please suggest what can i do to resolve this problem.

One confusion I am also having about this swap memory,Is this memory is a part of second memory that we can use as primary memory.

Please suggest.

Shivam

[debasissahoo · Accepted solution]

Shivam,

If buffers are getting full, then the configuration might be small. In ST06, the physical memory refers to RAM and swap space refers to the swap file at OS level.

For finding out which processes are taking much memory, you can use ST06 - detail analysis - top processes - checks the Residenz memory part. If you see some processes other than the usual sap and database process, then you may try to find out if you can stop/deschedule those to run at some other time.

Whats the total swap space configured?

[Former Member · Accepted solution]

Dears,

Swap configuration is:

Configured swap Kb 30.932.992 Maximum swap-space Kb 30.932.992

Free in swap-space Kb 26.645.220 Actual swap-space Kb 30.932.992

As RAM memory is also showing full and If I increase extended memory and buffer memory,Will it automatically occupy space from swap memory.

Shivam

[debasissahoo · Accepted solution]

Hi,

The memory used by SAP is taken from so called Virtual memory (RAM+SWAP).

For rectifying the current problem, if you increase the buffer or extended memory then, (yes) it should take further memory from the swap, but please keep in mind that this will increase the OS level paging as more and more part is used from swap.

You can try changing parameters in test environments to see any negative impact, but its strongly recommended to consult with SAP before changing parameters in Productive system.

Best Regards,

Debasis.

[Former Member · Accepted solution]

Ok Debasis,

Can you please suggest how much space I should increase in buffer and extended memory like 10% or 20%.

And what things I should remember while increasing their size.

Shivam

[debasissahoo · Accepted solution]

Shivam,

Follow the note 146289, for setting the parameters.

one thing to keep in mind, while changing em/initial_size_MB, make sure The value must be smaller than/equal to (%%em/blocksize_KB%% * 16) and an exact multiple of (em/blocksize_KB / 1024).

Thanks,

Debasis.

[Former Member · Accepted solution]

Hi Debais,

In my system em/blocksize_KB is 4096 KB that means 4096*16=65 MB could be the max size of my extended memory(em/initial_size_MB).

Shivam

[debasissahoo · Accepted solution]

Hi Shivam,

em/blocksize_KB = 4096

em/initial_size_MB (max) = 4096*16=65536 ~ 65 GB (not 65 mb)

- Don't get confused with the unit of these parameters. Please see the values and units come from the name itself. If in doubt see always go through ST02 > Current parameters. this will show you the value and unit side by side.

- Please see the maximum value allowed for em/initial_size_MB in RZ11 for your kernel also.

Regards,

Debasis.