Hi, any idea what version of Oracle that you are using :-) thanks for the info... well, there is a lot of debate on 'log file sync' and 'log file parallel write' and there is timing bug too. Look at BUG: 2669566. look at http://www.jlcomp.demon.co.uk/log_file_writes.html also, what was your setting for disk_async_io, filesystemio_options and _lgwr_async_io? did you modify any of these? thanks anand On 14/02/06, The Human Fly <sjaffarhussain@xxxxxxxxx> wrote: > > Hello list, > > Today we have a light smile on our face because we were struggling > with log file sync event on one of our business critical database. We > opened a TAR and implemented everything they have suggested. > Yesterday, we made litte changes, like, created a new mountpoint > enabling CIO (concurrent I/O) on AIX 5.3 using JFS2 filesystem, and > move our redo groups to this new mount point also increased the size > of redo groups from 512M to 1gb. > When we look at the log file sysn event in the statspack, it was just > vanished. Earlier, we used to get 40% as log file synce in the top > timed events and now it is just 3%. Its really a drastic change in the > wait event. > Now, I am planning to do the same for our datafiles, i.e. enabling cio > and moving the tablespace to new moutn point. Redo has only inserts, > but, for tables, we have read and write, does this can improve the > throughput? Will there be any performance gain? Does anyone using this > kind of option with JFS2 filesystem? > > Thanks for your time. > > -- > Best Regards, > Syed Jaffar Hussain > 8i,9i & 10g, OCP DBA > Banque Saudi Fransi, > Saudi Arabia > http://jaffardba.blogspot.com/ > > ---------------------------------------------------------------------------------- > "Winners don't do different things. They do things differently." > -- > //www.freelists.org/webpage/oracle-l > > >