Horton

Re: Memory usage during sorting

Tom Lane <tgl@sss.pgh.pa.us>

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From: Tom Lane <tgl@sss.pgh.pa.us>
To: Jeremy Harris <jgh@wizmail.org>
Cc: pgsql-hackers@postgresql.org
Date: 2012-03-18T15:45:47Z
Lists: pgsql-hackers

Commits

Same data as JSON: GET /api/v1/messages/:b64id/commits the thread's linked commits as JSON, with link sources. API reference →

  1. Improve performance of our private version of qsort. Per recent testing,

  2. Further performance improvements in sorting: reduce number of comparisons

Jeremy Harris <jgh@wizmail.org> writes:
> On 2012-03-18 15:25, Tom Lane wrote:
>> Yeah, that was me, and it came out of actual user complaints ten or more
>> years back.  (It's actually not 2X growth but more like 4X growth
>> according to the comments in logtape.c, though I no longer remember the
>> exact reasons why.)  We knew when we put in the logtape logic that we
>> were trading off speed for space, and we accepted that.

> How about a runtime check of disk-free?

Not very workable, the foremost reason why not being that it assumes
that the current sort is the only thing consuming disk space.  I'm not
sure there is any portable method of finding out how much disk space
is available, anyway.  (Think user quotas and such before supposing
you know how to do that.)

			regards, tom lane