value for parameter cache_size

[Former Member]

hello frindes,

i have a dell machine (1 proc) with 4 GB RAM and Suse Linux Enterprise Server 10 SP2 in 64 bit with MaxDB Software 7.6.03 in 64 bit. I want to install 2 (central-) instances (1. test and 2. PRD)in NUC ECC6.0 Standard only ABAP Stack.

Only max. 2 SAP-User should be work with this 2 instances. 3 DIA and 1 BTC of workprocesses per instances should be enough.

how much do I choose the parameter cache_size? i'm during the installation of the first instance an I chosse for the first test instance 600 MB. about a third from 2 GB per instance.

is this correctly?

many thanks for ideas ...

christoph

[markus_doehr2]

you have to make sure, the CACHE_SIZE and all the buffers and parameters you configure later in ST02 will not exceed the total available memory. Once the machine starts swapping, everything will be very slow.

So yes - 600 MB for both database instances is fine.

Markus

[Former Member]

hi and thanks,

buffers and parameters i configure with rz10 on istance profile - yes the fine tuning. swapping - i hope you mean not page in and out. i run on 64 bit with 12 GB /swap. i will see. 600 mb for both - ah okay. if i install the other instance, i must specify the cache_size parameter for the other Sysnumber 01 (other instance) also 600 mb. i tought i install the other instance and give the parameter again. then i have:

Instance:

[markus_doehr2]

> buffers and parameters i configure with rz10 on istance profile - yes the fine tuning. swapping - i hope you mean not page in and out.

I was talking about OS swapping.

> i run on 64 bit with 12 GB /swap. i will see. 600 mb for both - ah okay. if i install the other instance, i must specify the cache_size parameter for the other Sysnumber 01 (other instance) also 600 mb. i tought i install the other instance and give the parameter again.

Yes - you should be fine.

Markus

[Former Member]

here is the whole answer, sorry:

hi and thanks,

buffers and parameters i configure with rz10 on istance profile - yes the fine tuning. swapping - i hope you mean not page in and out. i run on 64 bit with 12 GB /swap. i will see. 600 mb for both - ah okay. if i install the other instance, i must specify the cache_size parameter for the other Sysnumber 01 (other instance) also 600 mb. i tought i install the other instance and give the parameter again. then i have:

Instances:

sysnr:00

cache_size = 600 MB

DBSID:SPK (instance 2)

rest of RAM for SAP: 2048 - 600 = 1448 MB

sysnr:01

cache_size = 600 MB

DBSID:SPP (instance 1)

rest of RAM for SAP: 2048 -600 = 1448 MB

600 MB for both, i dont understand.

thanks ...

[markus_doehr2]

You wrote:

> i will see. 600 mb for both - ah okay.

and later

> 600 MB for both, i dont understand.

??

Markus

[Former Member]

I meant :

i configure per db-instance 600 mb - not 600 mb for both.