Comment 15 for bug 635834

After looking around a bit for time degradation issues with Berkeley DB
(there are no visible reports), this thought occurs to me:

There's an optimization for DB_HASH access added to db-4.6.x.
As always, Berkeley DB provides backward compatibility but
perhaps the older DB_HASH layout is no longer optimal.
So the (hypothesized) result of doing --rebuilddb changes the
behavior to improve performance, but is not necessarily
time degraded, or fragmentation related.

I have no easy way to confirm the hypothesis. But RPM use
of Berkeley DB is quite straightforward and hasn't changed since forever.

And I expect -- because of wide usage -- that a performance time degradation with
Berkeley DB I/O performance would have been reported _SOMEWHERE_.

Does that sound consistent with what you are seeing?