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Message Posted: Mon, 11 Aug 2003 @ 10:02:57 GMT

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<-- Anonymously Posted: Sunday, August 10, 2003 22:09 -->

I think the key is not just how heavily utilized the system is, but how frequently the optimizer picks Hash Join; especially since HTMemAlloc is a per-query limit, not a system limit.

Setting it to 5% is a risk, in my opinion. It may influence the optimizer to pick Hash Join more often, and for larger spool files at that. Unless you have reserved a LOT of free memory, it would only take a few queries at 5% each to crash the system. If you DO always have lots of free memory, then lowering the Hash Table limit and expanding fsgcache would probably improve overall performance.

I'd at least want proof that some applications perform better with a 5% limit than with 1%...

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