Increasing Server Memory

[Former Member]

Hi All Expert,

I would like to ask, if we wan to increase SAP Server Memory (CIDBDI) is there any parameters need to adjust?

either OS / DB/ SAP Profile Parameters.

Im using SAP R/3 4.7 on HP-UX 11.31 and Oracle 10G Release 2.

Please advise,

Thanks all.

[former_member189546]

Hello,

Check notes

146528 "Configuration of R/3 on hosts with much RAM".

425207 "SAP memory management, current parameter ranges",

regards,

John Feely

[markus_doehr2]

Yes, this is not done automatically.

It depends on where you see bottlenecks and what your goal ist.

Markus

[Former Member]

HI Markus,

Thanks for Replied, but i still not clear for adjustment parameters in my OS/DB/SAP Profile Parameters.

[markus_doehr2]

There was a reason you upgraded the memroy, right?

Markus

[Former Member]

Hi Markus,

Of course there is a reason.

I have check from glance and OS06 the memory usage is almost 100%, my goal is to reducing memory usage below 90% and also increasing system performance.

so what information i need to collect so that i know what parameters should i adjust?

I wish there is SAP Documentation for memory upgrade that affect to system performance

[markus_doehr2]

> I have check from glance and OS06 the memory usage is almost 100%, my goal is to reducing memory usage below 90% and also increasing system performance.

This may also be caused by the filesystem cache of the operating system. As long as the system doesn't swap you're fine.

> so what information i need to collect so that i know what parameters should i adjust?

> I wish there is SAP Documentation for memory upgrade that affect to system performance

There is - but to use it you first need to know where you performance bottlenecks are, whether your "slow performance" is caused by the database, by the configuration or by memory. Just having the memory "in use" is not a key figure for an alledgedly "bad performance". If e. g. your database cache hitrate is 99 % it makes no sense to increase database caches, it won't help to get a faster system.

I would start with transcation ST03N (avg. dialog response time) and see where most time is used. I'd also check if the system is swapping (ST06). I'd also check the buffers in ST02.

There are too many factors influencing "performance" so there can't be general advise. If it would be that easy there wouldn't be the need to SAP services (Early Watch) to help to configure the system.

Markus

[Former Member]

so, do i need to configure SAP Early Watch?

i know there many factor that causing memory server utilization. But as i assume the memory server should be consumed below 85% good practices (CMIIW).

Regards,

sesario

[markus_doehr2]

> so, do i need to configure SAP Early Watch?

not necessarily if you can figure out how to configure

> i know there many factor that causing memory server utilization. But as i assume the memory server should be consumed below 85% good practices (CMIIW).

HP-UX uses filesystemcache also on VxFS so even if you put more memory in the server it may be used up at some point anyway because it's "available".

As I suggested I would start checking where the memory is actually used using the transactions I mentioned. Without knowing that reconfiguring is at best luck.

Markus