Perforamnce issue... (dbc_min_pct and dbc_max_pct)

[Hein van den Heuvel]

I don't have time just now for a full reply, but I must quickly comment on:

"So, should I increase dbc_min and max_pct, lets talk... to 5 and 10... And increase sga max size to 3Gb? "

No, no, no!

What you 'take' from DBC (1% = 40MB) you can 'give' to db_buffer_cache, or visa versa, but you can not increase DBA _and_ increase the SGA.

Well, with 50MB free you _could_ give 50 - 100MB away, but that would be playing it a little close to the edge.

Hein.

[Yogeeraj_1]

hi again,

i would also review the pga_aggregate_target parameter.

normally, you would start with about 500MB i.e. 1+ MB/connection

hoper this helps too!

kind regards
yogeeraj

[Eric Antunes]

Hi Jefferson,

Sorry for the delay.

Resuming, I recomend the followng:

1- Size dbc_min/max_pct until you have a %rcache greater than 90%

2- Your processes parameter is not consistent with your sessions one: Oracle derives sessions from processes with the following formula: (sessions = processes + 25). So you should set those 2 parameters more accordingly: increase processes to 500, for example.

3- As Yogeeraj said, use pga_aggregate_target instead of sort_area_size (sort_area_size is retained just for backward compability in Oracle 9i).

Best Regards,

Eric Antunes

[unimedriopreto]

Thanks all for explanations.