cancel
Showing results for 
Search instead for 
Did you mean: 

Query on rdisp/wp_auto_restart parameter

former_member190251
Participant
0 Kudos

Hello All,

In one of our production system, Paging usage is high eventhough physical free ram is available.

We have checked and found that we are not getting any memory dump (like PXA_NO_FREE_SPACE) in the

system. 

But we found paging usage is more eventhough there is no activity happened in the system and more physical RAM is avaliable

AIX team confirmed that everything is fine from their end.

Could you please let us know whether we can set rdisp/wp_auto_restart to 86400 S. Also let us know if there is any drawback / dependency need to be checked by setting this parameter.

Also please confirm if there is any paging parameter need to be reduced to resolve this issue

Enviornemnt

AIX 6.1

SAP ECC6.0

Oracle 11.2.0.3.10

Toa

ST02

OS level

Current Value of SAP Parameter

Paging parameters.

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

ipc/shm_psize_10 - 1472000000

rdisp/PG_MAXFS - 800000

rdisp/PG_SHM - 625000

rdisp/ROLL_SHM - 75000

ipc/shm_psize_40 - 562000000

EM/TOTAL_SIZE_MB - 31000

rdisp/wp_max_no - 115

rsdb/obj/buffersize - 1000000

rsdb/obj/max_objects - 250000

abap/buffersize - 3000000

abap/heap_area_dia -  4000000000

abap/heap_area_nondia - 4000000000

abap/heap_area_total - 8000000000

rdisp/accept_remote_trace_level - 0

rsdb/ntab/entrycount  - 200000

rsdb/ntab/ftabsize - 240000

rtbb/buffer_length  - 180000

rtbb/max_tables - 1500

zcsa/db_max_buftab - 42000

zcsa/table_buffer_area - 810000000

ztta/roll_area - 6500000

gw/accept_remote_trace_level - 1

Regards

Subbu

Accepted Solutions (0)

Answers (2)

Answers (2)

manumohandas82
Active Contributor
0 Kudos

Hi ,

Your Export/Import Buffer seems to be low  and could be increased by another 50% .  You may increase your program buffer too ( if its development )

Please check the following note

1971776  - High Usage of Paging Space on AIX        

902952  - AIX: Paging even though sufficient free memory

   

Also bring the following note to  the AIX teams notice

1972803  - SAP on AIX: Recommendations

Thanks ,

Manu

Former Member
0 Kudos

Hello Samb,

This note describes and proposes solution for your problem:

-78498 - High paging rate on AIX servers, in particular DB servers


Also you would check once more your settings per AIX-SAP note:

-1972803 - SAP on AIX: Recommendations

Section 4f

4f) Unexplainable usage of paging space

Sometimes an only slight overcommitment of physical memory, which should lead to only few percent of paging space usage, does lead to a seemingly quite high and long time increasing allocation of paging space. That can often be explained by an AIX optimization feature, keeping lot of "duplicate pages" in paging space, which is discussed in detail in Note 1971776.


Best Regards,

Serhat

Former Member
0 Kudos

Hi subu,

The Parameter is used to restart the workprocess automatically. And this helps when there is large amount of Paging and work process do not release memory even after restart or cancel with core scenarios.

With the help of this  parameter one can regain the memory and bring its utilization to normal.

Which avoids the instance restarts. Also refer to below notes which might help you to understand tha parameter

586824 - Restart SAP work processes for BW

922007 - Changing the parameter rdisp/wp_auto_restart dynamically

And do refer to Serhat recommendations for the parameters.

Let us know if this helps.

Regards,

Ram