Re: Subversion 1.9.0-dev FSFS performance tests

> Can you guys dig a little bit deeper here? Seems the performance
> regression that Ivan is seeing deserves some more investigation. With
> Ivan testing http: (and file:) on Windows, and Stefan testing svn: on
> Linux (with different cache settings) it's hard to see where the
> regression comes from.

There are the following main factors that lead to performance regressions:
* log addressing adds two additional files for each revision file
(that is obviously not good for unpacked repositories),
* the whole design relies on the enormous cache size (comparable to
the size of the repository itself).

> Right now, the numbers might just as well indicate that f7 is fast on
> Linux but slow on Windows. Or that it's only fast with svn: but slow
> with http:. That would be "not good".

The numbers do not depend on operating system so much. Stefan Sperling
has results that shows performance degradation on OpenBSD too. From
what I see,
FSFS7 may be fast when repository is packed and there is an enormous
cache size. It is slow when repository is unpacked (default) and cache
size if adequate (default).

-- 
Ivan Zhakov