Was 10G and UFS - long write times (is, I/O really?)

        PS the waits are all IO related - log buffer , log file sync etc

... are you absolutely sure the I/O component of these waits is what is actually slow.
You know there is more to the anatomy of a log file sync and log buffer wait than
I/O right? A process get posted though the post/wait mechanism (port dependent)
and THEN it comes out of the wait. In short, there is IPC wrapped around the LGWR
loop. I wonder if there is something in the 10gR2 post/wait driver that is busted?
Quite possible. How do they compare with _logging_disable=TRUE? When this is set there
is still LGWR posting and lfs waits, but LGWR doesn't actually write to the log.

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