Well the real culprit would be log file switch (checkpoint incomplete) there is possibility that your i/o bandwidth is very low. You can try increasing logfile size to see if this can give some time to write to logfiles. On Wed, Jul 28, 2010 at 1:18 PM, Yadavalli Aditya < aditya.yadavalli@xxxxxxxxx> wrote: > Hi All, > > I am seeing poor performance with one of the 11gR2 instances, and when > i ran statspack reports for the time period , i am seeing "db file > async I/O submit" wait event on the top hitting almost 56%. I have > checked metalink as well as google, did not get any information. > Please share your experiences if any one has seen this before. here is > the snapshot (numbers are galbled, please excuse!) > > > Top 5 Timed Events Avg > %Total > ~~~~~~~~~~~~~~~~~~ wait > Call > Event Waits Time (s) (ms) > Time > ----------------------------------------- ------------ ----------- ------ > ------ > db file async I/O submit 13 53 4068 > 56.2 > log file switch (checkpoint incomplete) 4 27 6808 > 28.9 > CPU time 6 > 6.2 > log file parallel write 1,452 5 4 > 5.8 > control file parallel write 65 1 20 > 1.4 > > Thank you, > Aditya > -- > //www.freelists.org/webpage/oracle-l > > > -- Thanks & Regards, Taral Desai