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TUNNING REDO LOGS AND LOG_BUFFER

user-galan_josel_8777750Sep 3 2008 — edited Sep 18 2008
Oracle: 10gR2 -> 10.2.0.1
OS : Linux Redhat Release 4 update 5
FS : OCFS2


We are having a very high REDO LOGS generation. We have been increasing the REDOLOGS size.
Redologs SIZE now are 1GB and we have 3 groups.
We are now at 300-500 redologs swithes a day. When we should be < 90.
We can fix that increasin the size of the redologs.

But checking in general the database we found.

log_buffer = 30571520 = 30MB. By oracle standards this parameters is high.

redo blocks written 2462945123
redo buffer allocation retries 450827

SELECT name, value FROM v$sysstat WHERE name = 'redo log space requests';
redo log space requests 142000

The value is very high.

SELECT substr(ln.name, 1, 20), gets, misses, immediate_gets, immediate_misses
FROM v$latch l, v$latchname ln
WHERE ln.name in ('redo allocation', 'redo copy')

redo copy 569 6 2698328537 121730
redo allocation 6822319 53651 2698212924 2803626

The redo copy is over 1%

I'm looking for any misconfiguration in the database other than the redolog size increase.
Is the size of the log_buffer impacting?
What others parameters I should be looking?

Any other ideas what to look for is welcome.


Thx Jose
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Locked on Oct 16 2008
Added on Sep 3 2008
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