Performance branch - svnserve crash in fs_history_prev

Hi,

I've taken the performance branch for a spin. Some of performance
increases are awesome (svn log is ~4 times faster on my machine
(tested with a file with 300 revisions)).

However, I also experienced a crash of svnserve, for both "svn log"
and "svn blame" of a big file with >2000 revisions (so this is quite
an extreme case). See both .log files in attachment. Something goes
wrong in svn_fs_fs__id_deserialize, during processing of
fs_history_prev.

I also have crash dump files of the crashes. If you want those, let me
know and I'll send them via private email.

This was on Windows XP, a release build with VCE 2008.

Cheers,

-- 
Johan