Regarding increase in background processes

[Former Member]

Hi,

The RAM in our BW systems has been increased by certain amount.

This is because there will be more jobs running in the production system due to some projects which will be transported to production.

Hence, we need to increase the background processes in the production system (on two application servers and central instance) to utilize the additional increase in RAM.

Could you give us a rough idea how to proceed forward?

Also, is there any need to increase the update processes in the system?? There is currently only one UPD and one UPD2 process in the central instance, and none in the application servers.

Kindly let me know.

Thanks & Regards,

Kunal.

Edited by: Kunal Patel on Apr 14, 2010 9:17 PM

[Former Member · Accepted solution]

Quantity of work process is defined in instance profile located in CI directory /usr/sap/<SID>/SYS/profile/<SID>_DVEBMGS<nn>_<hostname> by parameters below:

rdisp/wp_no_dia -- dialog

rdisp/wp_no_btc -- background

rdisp/wp_no_enq -- enqueue

rdisp/wp_no_vb -- update

rdisp/wp_no_vb2 -- update2

As a rule of thumb, quantity of dialog process should be no less than sum of all other processes for CI, and enough UPD processes on CI determines performance for database activities, the proper amount of which comes from a thorough performance history. Simply put, you need to keep observing and then will come up with a best setting in your case.

Regards,

[Former Member · Accepted solution]

Hi,

Thanks for your reply...

But could you let us know some other method of determinig this besides the R&D i.e. some thumb rule...

We have in both (two) application servers work processes distribution as below:

Dialog: 35 during day and 30 during night using operation mode

Bgd: 10 during day and 15 during night (by using operation mode)

spo:1

In Central Instance, distribution as below:

Dia: 6

Bgd: 2

Spo: 1

Upd: 1

Upd2: 1

Enq: 1

Your comments are welcome...

Regards,

Kunal.

Edited by: Kunal Patel on Apr 15, 2010 1:45 PM

[Former Member · Accepted solution]

Hi Kunal,

If you don't have waits on the update process, there is no need to add an additional.

In transaction sm50 -> list -> cpu, you can see the usage of your processes. So if you have a lot of dia processes that are hardly being used, you could change these into bg.

I see that you have configured 2 bg processes on the CI. I would change these into dia or one dia and one upd.

Kind regards,

Mark Dijsselbloem

[Former Member · Accepted solution]

> In Central Instance, distribution as below:

> Dia: 6

> Bgd: 2

> Spo: 1

> Upd: 1

> Upd2: 1

> Enq: 1

With that many dialog processes on DIs, the configuration for CI doesn't look correspondingly powerful, like a possible minimum work processes for a CI instead. Although BW is not an OLTP system, but this 6 dialog processes plus one upd process is not equivalent if DIs need that many dialog processes to work with end users. Have you experienced any performance issue on DIs or any long waiting for end users?

Note 39412 - How many work processes should be configured?

Regards,

[former_member126060]

Hello Kunal,

Check SAPnote # 39412 (How many work processes should be configured?). This have standard recommendation and calculation regarding the work processes.

You may also find SAPnote # 108799(How many spool work processes for each instance?) helpfull.

Best Regards

Niraj