Reg:Swaps in ST02

[Former Member]

Hi Gurus,

I have been seeing lot of swaps occuring in ST02,in one our production servers.

I could see the swaps occuring on CUA buffers in huge volumes

Can any body give me any clue on how to go about it,interms of analysing the swaps and fixing the same

Your help would highly be appriciated

Thanks in advance

Rgds-

Venu

[Former Member · Accepted solution]

Hello,

All buffers with the exception of the ABAP Program Buffer should normally have zero swaps. If you do see swaps then there is little you can do except enlarging the buffer. Always check whether you have to enlarge the buffer size, the number of directory entries in the buffer, or both. ST02 shows both the free space in the buffer and in the directory. To determine which parameters to change, double-click on the buffer and on the next screen click on "Parameters".

There is no absolute rule for the extra space you have to give to the buffer. However, as the CUA buffer is normally relatively small, I would give it a 50% size increase right away.

All buffer parameters are static, so you will have to restart all the instances of your system in order to activate the change.

Regards,

Mark

[Former Member · Accepted solution]

The issue has been resolved after the Patch upgrade

Thanks

Venu

[Former Member]

Hi

Please perform a periodical restart of the system.It will impove the performance

Regards,

Sukarna

[Former Member]

hello

you will find some help here : [Online help about buffers|http://help.sap.com/erp2005_ehp_04/helpdata/EN/c4/3a6e98505211d189550000e829fbbd/frameset.htm]

"When a buffer has insufficient freespace or free directories, it has to swap objects out of the buffer in order to load a new object. The column Swap shows how many objects have been swapped out since system startup."

This means that you have to increase the size of the buffer to avoid swapping.

To find the relevant parameter (in RZ10) for a specific buffer => transaction ST02, double click on the buffer and then click on the button "Current parameters". Here is/are the parameter(s) to increase (be careful of some parameters ... your system can crash or not restart !)

After saving & activating the profile in RZ10, perform at os level the command (under <sid>adm) : sappfpar check to fix the memory problems.

Hope this will help you

[Former Member]

hi venu,

If there are lots of swapping happening(this means your buffer size is smaller and can't accomodate all the obejcts),I would suggest you to increase the size of buffers...that is the best way to approach this

Change the value of rsdb/cua/buffersize parameter in your profile and increase it approx to 20-25 % of the current value and restart the system

Also make sure that buffers hit ration in ST02 is high..should be close to 99%

Rohit