Re: Threaded Sorting

Hans-Jrgen Schnig wrote:
> Threads are bad - I know ...
> I like the idea of a pool of processes instead of threads - from my
> point of view this would be useful.
>
> I am planning to run some tests (GEQO, AIX, sorts) as soon as I have
> time to do so (still too much work ahead before :( ...).
> If I had time I'd love to do something for the PostgreSQL community :(.
>
> As far as sorting is concerned: It would be fine if it was possible to
> define an alternative location for temporary sort files using SET.
> If you had multiple disks this would help in the case of concurrent
> sorts because this way people could insert and index many tables at once
> without having to access just one storage system.
> This would be an easy way out of the IO limitation ... - at least for
> some problems.

Bingo! Want to increase sorting performance, give it more I/O
bandwidth, and it will take 1/100th of the time to do threading.

Ingres had a nice feature where you could specify sort directories and
it would cycle through those directories while it did the tape sort.

Added to TODO:

* Allow sorting to use multiple work directories

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