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Subject: Re: Eugene, etc. Hardware question.

Author: Eugene Nalimov

Date: 14:58:05 04/02/03

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Looks like some cache conflict to me.

Are you sure your TREE structure is 128-bytes aligned? If not you can end up
having 2 structures one after another in memory, and end of 1st structure and
beginning of 2nd one will be in the same cache line. Each time one CPU is
writing data to that cache line it invalidates data in the 2nd CP cache. And you
happen to have frequently used fields both in the beginning and at the end of
the structure...

Assuming that all your TREE structures are dynamically allocated, fix is easy.
Allocate them exactly as you are allocating entries in the hash table.

Or you can just move large move array to the end of the structure. I assume that
you are not using the entire array too often...

Thanks,
Eugene



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