Thumbrule to size SGA

Hi frnds,
Is there any standard policy/thumbrule to size the SGA. How do i size memory structures based on number of expected users? Will that be a right move?

Thanks,
Kam

Hi Friend,

For me I allocate 5Mb-10Mb per user :)

Hi,
How did you arrived that figure? What is the logic behind that?

Thanks in advance

Well, from some statistics that an average process being invoked by
users consume 5Mb memory, and i read somewhere that it can be 1/4 of the physical memory. Then adjust it accordingly as no. of users increases. :)

Hi,
U mean SGA to be set 1/4 of Physical mem? I suppose ideal shd be 65% of Physical mem. Could anyone validate this answer?

Thanks.

I mean the total SGA :rolleyes:

Quote:

---

Originally Posted by Kamkan

Hi,
U mean SGA to be set 1/4 of Physical mem? I suppose ideal shd be 65% of Physical mem. Could anyone validate this answer?

Thanks.

---

I have a server with 48GB physical memory and 6 instances running, dont think the rule you have heard about can be used.

May I know what are the total SGAs you used Pando? If I have
that BIG MEMORY, I think I will start my SGA with 4Gb as baseline then adjust/tune it as I go along. Its just really in my instinct :)

Hi,
Yes Pando. I agree. Is there any ideal way to calculate the mem requirements?

Can anyone help to come out with clear idea?

Thanks,
kam.

There is no perfect rule in allocating memory for SGA, PGA, etc; and it varies system to system.
You need to monitor the processes, collect statistics over period of time, and adjust the memory requirements accordingly.

Tamil