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Re: proxy-cache

> Pierangelo Masarati wrote:
>>>didn't your fixes to the sql backend for searching auxiliry
>>>objectclasses make it to 2.2.17? It seems not, which is a pitty....
>> I haven't had much time since way before 2.2.17 was being released, and
>> the inclusion of that fix is not straightforward because it's very
>> intrusive in some code that is HEAD only (2.2 is feature-frozen right
>> now).  Sorry...
>> p.
> Ok, I understand. I do wonder, did anything change in the back-sql code
> since that particular fix? I'm now seeing a decrease in performance by a
> factor 4 on the exact same database. I used to be able to retrieve 1079
> entries in about 1m45s, with my recent update of HEAD to the code as it
> was yesterday, that same search takes about 9m30s, this is without the
> effect of the proxy-cache, which seems to decrease performance
> drastically (another factor 2 or so) for the initial search. Of course,
> subsequent searches are a lot faster (5 sec for the same 1079 entries),
> so the cache does work.

There were no changes between 2.2.15 and 2.2.17; there are lots of changes
between 2.2.17 and HEAD; at a first glance there's not much that should
impact performances.  There's a small issue, I had to change the way
schema mapping is looked up; at some point it was done by comparing
pointers, but that made tests not portable because attribute ordering in
the results was machine or even run-time dependent; so I made it default
to strcmp based.  I haven't noticed significant performance impact, but I
never used very large databases.  You can revert to the old behavior by
recompiling back-sql (actually, all you need to recompile is schema-map.c)
with -DBACKSQL_USE_PTR_CMP (see the comment at the beginning of

This may (and will) cause sql-test* fail because the results are not
ordered as in the reference.

Anybody please holler if you find a better way to sort results in a better


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Pierangelo Masarati

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