Determing Amount of RAM Being Used by oracle 1

[Michael42]

Hello,

On an E25k Sun System running Solaris 10 I am having a hard time interpreting prstat concerning the amount of RAM being used by a service. If I run prstat -atv it shows oracle as taking up 98% of the system memory.

NPROC USERNAME SIZE  RSS MEMORY  TIME     CPU
----------------------------------------------
45    oracle   63G   61G 98%     7:31:51  17%

I am not convinced this is correct as I have a hard ceiling on how much memory oracle can use (via SGA_MAXSIZE=2G and PGA=1G). It is a new system and there are no users on it yet.

top (selecting u and oracle) seems to show multiple 2G chunks being used. I am confused.

Can you please help me understand why prstat -atv is reporting this?

Thanks,

Michael42

 

[Annihilannic]

Unfortunately Solaris has never been very smart about reporting the use of shared memory (nor can I think of a sensible way that it *could* report it really), so if you have multiple processes using the same shared memory area, in this case the 2GB SGA, then Solaris will add all of those up to arrive at the massive figure you see.

I haven't seen Oracle running on Solaris 10 yet, but the best you can do I think is look at the free memory on the system as reported by swap -s to see what memory *isn't* being used by Oracle. You can see the shared memory areas from ipcs -m.

Annihilannic.

 

[Michael42]

Annihilannic,

Thanks for posting. Those commands are very useful.

-Michael42