Re: Memory Usage in Oracle

Ok I think I know why Oracle wants more and more RAM. Upon Oracle's recommendation, we set certain parameters within the /etc/security/limits file. One of those parameters is for memory w/ the "unlimited" parameter.

Does anyone else have this set? (ulimit -a)

Also if Oracle does use more and more RAM, won't it eventually consume all available RAM, thus causing the system to page when it reaches that threshold?

I'm I worrying too much?

Thanks!

EscVector wrote:
> jeffchirco_at_gmail.com wrote:
> > Oh and the system does not page.
>
> You are top posting, someone will yell at you....
>
> Have you checked which processes are eating up your memory at the os
> level.
> I mean, which Oracle process is actually eating up the memory and then
> check that in v$session/v$process?
>
> This would be a good start.
>
> Run nmon for the period in question and then process via the nmon
> analyzer.
> http://www-128.ibm.com/developerworks/aix/library/au-analyze_aix/
>
> select * from dictionary where table_name like '%PGA%';
> Check v$pgastat
>
>
> Example from AIX system dev system:
> 5.3.0.42
> AIX53
> Architecture PowerPC Implementation POWER5 64 bit
>
> 17:07:49 SYS_at_test> select * from v$pgastat;
>
> NAME
> VALUE UNIT
> ----------------------------------------------------------------
> ---------- ------------
> aggregate PGA target parameter
> 157286400 bytes
> aggregate PGA auto target
> 91855872 bytes
> global memory bound
> 31457280 bytes
> total PGA inuse
> 55306240 bytes
> total PGA allocated
> 133772288 bytes
> maximum PGA allocated
> 438723584 bytes
> total freeable PGA memory
> 6750208 bytes
> process count
> 20
> max processes count
> 31
> PGA memory freed back to OS
> 6.1152E+10 bytes
> total PGA used for auto workareas
> 0 bytes
> maximum PGA used for auto workareas
> 142358528 bytes
> total PGA used for manual workareas
> 0 bytes
> maximum PGA used for manual workareas
> 1075200 bytes
> over allocation count
> 1
> bytes processed
> 2.7145E+11 bytes
> extra bytes read/written
> 3.0147E+11 bytes
> cache hit percentage
> 47.38 percent
> recompute count (total)
> 205849
>
> 19 rows selected.
Received on Fri Jan 12 2007 - 10:15:44 CST