commit_write Performance

This 10g new parameter looks behaves much different with combination of values. and it is not very clear documented .

listing my testing result below

commit_write value SQL perf Remarks
immediate,wait 9:28 "log file sync" oberserved
null, null 1:21
immediate,nowait 1:54
batch,nowait 1:10
immediate 1:17
batch 1:07
batch,wait 10:20 "log file sync" oberserved