Re: [HACKERS] \dt and disk access (fwd) - Mailing list pgsql-hackers

From Bruce Momjian
Subject Re: [HACKERS] \dt and disk access (fwd)
Date
Msg-id 953aed959db4fc04b87a19ae14ad74f4
Whole thread Raw
List pgsql-hackers
> The psort() code is designed for sorts that would clearly fill the
> shared buffer pool and disk buffer pool.  It takes a multi-megabyte
> ORDER BY to do that on my machine.
>
> And I am using a Barracuda Ultra drive with tagged queueing doing 7
> Mbytes/second transfers, so I am not testing this on a slow drive when I
> report 0.23 seconds to sort one row.

I have looked over the Mariposa psort() code, and it does prevent the
copying of data into a temp. table.

However, it still has problems.

    mktemp's, creates, opens, closes. unlinks seven files every time

    stores sorted results in file, rather than in memory if possible

- --
Bruce Momjian
maillist@candle.pha.pa.us

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