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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.

Jan

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