Windows x64 + Oracle 10g + 32 GB RAM

[CLOEFFLER]

Hi Everyone,

we just set up a new central system with 8 CPU's and 32 GB RAM,

running Oracle 10g and SAP 4.70X200 on Windows x64.

Does anybody has already experience with optimum memory settings

for that amount of memory and SAP. I setup the system using the

notes 88416 + 103747 + 146289 (Parameters 64bit Kernel), giving

SAP 12 GB RAM and Oracle 8 GB RAM, but using em/initial_size

instead of PHYS_MEMSIZE.

System is running pretty well but I would like to get best of out if it.

Thanks in advance.

Carsten

[markus_doehr2 · Accepted solution]

I would give the maximum amount of memory to the database, not to the application server. In "earlier days" the rule of thumb was - have 10 % of the database size in the memory (sga_target_size).

However, depending on the number of users using the system and what applications/modules you run this ma vary.

I´d start with 20 GB for the database and the rest for the SAP system. The less the database needs to physically read from the harddisk the faster your system will be.

--

Markus

[Former Member · Accepted solution]

my recommendation would be to start with 1/3 for the database and 2/3 for the SAP application server.

But as you said, this depends on the number of users and used transactions.

peter

[CLOEFFLER]

Thanks a lot for your advise. What I learned is, that my thread was too

unspecific so I give you a more details on this:

- We have about 150 users using IS-U/CCS in SAP ERP 6.0 ABAP

- This is a central instance running Oracle 10

- We do not have any more application servers.

What I learned long time ago - and this is what the mentioned notes still say -

give 30 % to the database and give 70 % to SAP. In my case this should be

about 10 GB for Oracle, and 20 GB for SAP.

Right now is set to: 8 GB Oracle and 12 GB SAP.

Running and installing SAP over the years, my experience is, that you better

should configure 30 % for SAP as well because it draws a lot more memory

than just simply the PHYS_MEMSIZE.

But I do not have enough experience with that amount of RAM.

Now we are productive on the second day and what should I tell you: I already

have some jobs cancelling with dump "MEMORY_NO_MORE_PAGING".

Maybe this is because I used the parameters of note 146289. I deleted them

but have to restart SAP tonight, because I believe that they cut off memory.

As well I decided to use PHYS_MEMSIZE instead of EM/INITIAL_SIZE. What I

read from several notes and messages that EM/INITIAL_SIZE only works up to

8192 MB.

On the other hand I made some bad parameter decisions in Oracle as well.

So I will come back tomorrow maybe after the restart.

Thanks again so far.

Kind Regards,

Carsten Loeffler

[Former Member]

Hello,

In your case a good start may be the default 10 GB for Oracle and 20 GB for SAP.

Then you have to observe your system with the production load and make adjustments accordingly : this the "art" of tuning.

In my experience, whatever amount of memory you allocate to SAP, users will always find a way to create memory related short dumps !

The key is to find the right tuning to get the short dumps only for unresonable requests.

Regards,

Olivier

[Former Member]

>>Now we are productive on the second day and what should I tell you: I already

>>have some jobs cancelling with dump "MEMORY_NO_MORE_PAGING".

MEMORY_NO_MORE paging is typically related to a shortage in the Page Area (see ST02). rdisp/PG_SHM has normally to be increased.

The Page Area is not related to em (extended memory) and is - if not explicitly set - calculated in dependence of PHYS_MEMSIZE. It may happen that this algorithm is not right for all transactions and configurations.

peter

[CLOEFFLER]

Hey Everyone.

I just want to update to. I've learned that notes 88416 and 103747 are

still the best, even if you have 32 GB and a central instance Plus the

information on rdisp/PG_SHM that Peter Simon gave.

System is now quite stable and very fast (Dia < 150 ms).

Thanks to everyone.

Regards

Carsten Loeffler

[Former Member]

Hi,

It depends a lot if you have also app servers.

If yes you have to decide if the CI is also designed to share the users load.

We have a production system where DB/CI are on the same physical server and with 4 app servers. we decided to have no users connections and no jobs on the CI. So the memory is mainly allocated to the database on this server.

It really is a choice specific to each company....

Regards,

Olivier