thanks to all for the info... this is a sun-fire v890 48G of memory and 6CPU. this is a new problem after upgrading to 11gR2. it is sporadic... i want to say it is encountered mostly when there is commit intensive jobs running. oracle has recommended setting _db_fast_obj_ckpt and _db_fast_obj_truncate to false to see if they alleviate write complete waits and enq: KO - fast object. thanks -doug- -- //www.freelists.org/webpage/oracle-l