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From Jan Hlavatý <hla...@code.cz>
Subject Re: java1.4.2 "rws" mode - log write performance - OSX numbers
Date Wed, 15 Sep 2004 19:35:40 GMT
Michael.Giroux@objectweb.org wrote:
> On the survace, test #11 and #15 appear to be very similar, yet there is
> a 14x improvement in #15.
> Does anyone know enough about the IO to be able to explain why
> "rw" write+force is 14x slower than "rwd" write?
> Reading the Javadocs, using "rwd" the write blocks until the data is
> on disk.  With "rw" the write does not block, but the force(false) 
> does block. Since the same amount of data is involved in both cases,
> can anyone explain why the "rwd" write is so much faster?

Most probably because the implementation does not what it is supposed to do,
and does ordinary "rw" mode instead.


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