What about Steve Adam's comments at:
http://www.ixora.com.au/tips/tuning/log_buffer_size.htm
What results have been achived by tweeking _log_io_size settings?
I was about to poke around with this.
Of course, it is not necessary to carefully balance log buffer space
waits against
Title: RE: log_file_sync io wait question
well if you have mirrored members that exist on the same disk thats an
issue, if this same disk houses the currently used datafiles that would
add to the situation. I placed my redo on a seperate raid-1 and dropped
the member mirrors and see better
Have you played around with the size and number of your redo logs? Larger redo logs
would mean fewer checkpoints.
Dropping redo log member mirrors is tempting, but RAID alone isn't enough protection.
I experienced a corrupted file system one time, and I was glad that my redo logs were
There are all sorts of things you can do to speed up
the process of writing log files:
a) direct io file systems
b) isolate logs onto disks
c) raw
d) faster disks
e) ultra fine grain striping
f) transaction_auditing = false
etc etc etc...but the big key here is:
Each and every record is
Hi Pat
There is not a lot you can do since every commit will force a write to
the disk !
You are hitting that limit of the disk that normally is app. 100 - 120
I/O per sek.
The only real fix is change the application to do less commit's.
It will not help to change the size of the redo log
