Horton

Re: Memory usage during sorting

Jeremy Harris <jgh@wizmail.org>

View thread
From: Jeremy Harris <jgh@wizmail.org>
To: pgsql-hackers@postgresql.org
Date: 2012-03-18T15:32:50Z
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

On 2012-03-18 15:25, Tom Lane wrote:
> Jeff Janes<jeff.janes@gmail.com>  writes:
>> On Wed, Mar 7, 2012 at 11:55 AM, Robert Haas<robertmhaas@gmail.com>  wrote:
>> The problem there is that none of the files can be deleted until it
>> was entirely read, so you end up with all the data on disk twice.  I
>> don't know how often people run their databases so close to the edge
>> on disk space that this matters, but someone felt that that extra
>> storage was worth avoiding.
>
> 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?
-- 
Jeremy