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Re: Memory usage during sorting - Mailing list pgsql-hackers

From Greg Stark
Subject Re: Memory usage during sorting
Date
Msg-id CAM-w4HNQh8b8qw5ziL5pYfCe16iVEKV8DzQffn=7csvpf1GQzg@mail.gmail.com
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In response to Re: Memory usage during sorting  (Tom Lane <tgl@sss.pgh.pa.us>)
Responses Re: Memory usage during sorting  (Tom Lane <tgl@sss.pgh.pa.us>)
Re: Memory usage during sorting  (Robert Haas <robertmhaas@gmail.com>)
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On Tue, Mar 20, 2012 at 1:57 AM, Tom Lane <tgl@sss.pgh.pa.us> wrote:
> That was a long time ago, of course, but I have some vague recollection
> that keeping next-run tuples in the current heap achieves a net savings
> in the total number of comparisons needed to heapify both runs.

Offhand I wonder if this is all because we don't have the O(n) heapify
implemented.

-- 
greg

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