Export/Import Buffer tuning (ST02)

[Former Member]

In preparation for go-live I am tuning the buffers on our ECC system, I noticed lots of 'Red' in our ST02 statistics (See ST02 attachment). I
have read online that if you hit ratio is over 96% on your buffers than
you are likely in good shape - is this true?

I noticed our export/import buffers have a low hit ratio (See ST02 attachment). What can I do to raise this hit ratio? Attached you will find
the 'Export/Import Settings' and 'Export/Import Parameters' that we have in place. We have random people complain of performance issues,
but they seem to pass over time. At max we only have had 20 or so people on the system at once when we
here the complaints, so we are concerned when we go live with 1000 users we
are going to have major issues.

We have a 5 application server Windows 2008 R2 setup backended into SQL 2008 R2. All are virtualized and share identical 
RZ10 parameters. All servers have 15G of RAM and have a system managed page file, with no upper/lower limit specified. What can I do to improve myhit ratio for export/import settings?

Thanks in advance for any guidance

[Former Member · Accepted solution]

Hi Steve,

Export/Import buffer size is relatively small what I see here, though it depends from system to system. I have seen in the ranges of few GBs. Swapping in the range of millions should be avoided if you have enough main memory available. You can increase the Exp/Imp buffer which will improve the Hit Ratio.

Again, Hit Ratio is not the only indicator of your buffer being in a happy state or as a sound performance criteria. Since you are going for a Go Live with a spike of users, you should consider increasing other buffers as well e.g. Program Buffer.

For performance issue, it needs to be tackled case by case basis and root cause needs to be identified.

Thanks,

Samik

[ralf_wahlen3]

Hi Steve.

Use that SAP Notes for the rsdb/obj buffers:

especially this one: Note 702728 and this Note 649613 +

Note 373986

Note 8778

Note 480710

Greets Ralph

[Former Member]

Thanks everyone for the advise. I have bumped our parameters and are monitoring accordingly.

[Reagan]

Hello

For Export/Import Parameters I suggest you to increase them by 30% of the present value.

Tuning can be done based on the system usage and not based on assumptions.

Cheers

/ RB /