log_buffer settings

From: Steve Perry <sperry_at_sprynet.com>
Date: Sun, 26 Sep 1999 10:52:45 -0700
Message-ID: <7slfc7$bcb$1@nntp3.atl.mindspring.net>

Can anyone help out with "realistic" settings for the log_buffer parm, as well as anything else I might want to check? I have kept increasing the log_buffer parm to 16meg now, but still keep seeing the waits below. I changed the log_simultaneous_copies to 16 (2 x #cpu's), but nothing seems to help. The below was from a 2 hour window when normal activity was taking place. It's an OLTP system (400 concurrent users), Oracle 7.3.4, aix 4.3.2 (4 gig of ram), sga of about 700 meg, 250 meg of shared pool. The Oracle manuals state that increasing the log_buffer beyond 1 meg does no good, but I've heard otherwise. It hasn't made any difference for me... There must be something I'm missing.

from utlstat report (system statistics)

Statistic                                     Total   Per Transaction    Per
Logon      Per Second
redo log space requests        10,998                      .03
38.73                 1.19
redo log space wait time  1,070,620                    3.38      3,769.79

115.96

Thanks,
Steve Received on Sun Sep 26 1999 - 12:52:45 CDT