On Wed, 30 Jun 2004, Mark Moynahan wrote: > Currently, we have an ODS system with 3 redo log files sized at 200M each. > Looking at v$log_history, the logs are switching every 1 to 2 minutes. If a > 200M log switches at 2 minutes then a 400M log should switch in 4 minutes > and 1G log should switch in 10 minutes. I've recommended to size the redo to > 1G along with determining what is causing all the redo with Logminer. Is 20 > minutes a good rule of thumb to go by when seeing how often the redo logs > switch? If checkpoints and archiving are keeping up, then I can't think of a good reason logs shouldn't switch every 2 minutes. You don't need logminer to find the redo culprit, just this SQL: select module, osuser, sql_hash_value, value / (sysdate - logon_time) redo from v$session s, v$sesstat ss, v$statname sn where s.sid = ss.sid and ss.statistic# = sn.statistic# and name = 'redo size' order by redo; -- Jeremiah Wilton http://www.speakeasy.net/~jwilton ---------------------------------------------------------------- Please see the official ORACLE-L FAQ: http://www.orafaq.com ---------------------------------------------------------------- To unsubscribe send email to: oracle-l-request@xxxxxxxxxxxxx put 'unsubscribe' in the subject line. -- Archives are at //www.freelists.org/archives/oracle-l/ FAQ is at //www.freelists.org/help/fom-serve/cache/1.html -----------------------------------------------------------------