Re: log file sync vs log file parallel write probably not bug 2669566

From: HansP <>
Date: Wed, 5 Nov 2008 23:51:23 -0800 (PST)
Message-ID: <>

> This is a wild guess, based on the 10g docs, which may or may not
> apply or work the same:
> The log file parallel write includes the I/O time only.  The log file
> sync includes the time the log writer has to wait for the db writer
> to
> tell the log writer the redo is done (all those "private strand flush
> incomplete" notifications in the 10g alert log), as well as all the
> other
> overhead of the interprocess communication.
> jg
> --
> is bogus.
> Ya win some, ya lose some.

Yes the includes waiting for the log file parallel write by the log writer and some overhead (signalling each other etc) Therefore I would expect the for the log file sync be a little more than the time for the log file parallel write but not 10 to 20 time the
time for the log file parallel write.

regards Hans-Peter Received on Thu Nov 06 2008 - 01:51:23 CST

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