Re: Performance problem in aset.c

At 01:21 12/07/00 -0400, Tom Lane wrote:
>Philip Warner <pjw@rhyme.com.au> writes:
>> Can you maintain one free list for each power of 2 (which it might already
>> be doing by the look of it), and always allocate the max size for the list.
>> Then when you want a 10k chunk, you get a 16k chunk, but you know from the
>> request size which list to go to, and anything on the list will satisfy the
>> requirement.
>
>Maybe the right answer is to eliminate the gap between small chunks
>(which basically work as Philip sketches above) and huge chunks (for
>which we fall back on malloc).  The problem is with the stuff in
>between, for which we have a kind of half-baked approach...

That sounds good to me. 

You *might* want to enable some kind of memory statistics in shared memory
(for a mythical future repoting tool) so you can see how many memory
allocations fall into the 'big chunk' range, and adjust your definition of
'big chunk' appropriately.


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