*** 2011-09-14 09:30:04.947
Warning: log write time 500ms, size 0KB
*** 2011-09-14 09:33:41.058
Warning: log write time 560ms, size 3KB
*** 2011-09-14 09:48:55.597
Warning: log write time 820ms, size 0KB
*** 2011-09-14 10:00:50.477
Warning: log write time 870ms, size 0KB
The problem surfaced after upgrading to 10.2.0.4.
The above warning messages has been introduced in 10.2.0.4 patchset. This warning message will be generated only if the log write time is more than 500 ms and it will be written to the lgwr trace file .
These messages are very much expected in 10.2.0.4 database in case the log write is more than 500 ms. This is a warning which means that the write process is not as fast as it intented to be .So probably you need to check if the disk is slow or not or for any potential OS causes. If everything looks fine at the hardware level or OS level then you can safely ignore these messages. The trace file can easily be deleted or truncated.
the error may be suppressed by setting Event 10468 level 4.
alter system set events ’10468 trace name context level 4′;
ALTER SYSTEM SET EVENTS ’10468 trace name context off’;