Re: Parallel updates on multiple cores

On Mon, 2008-06-09 at 01:29 -0700, Andrei wrote:
> The function above updates the rows between the ids start_id and
> end_id.
> I have a quad core procesor so i run two separate connections to the
> database: select populate_test_data(5000,1) and another select
> populate_test_data(5000,2). In this case each function runs on one
> core doing the inserts in parallel, but when i try to run select
> select_unprocessed(1,5001) and from another connection select
> select_unprocessed(5001, 10001), one of the processes locks the table
> so the other one has to wait until the table is unlocked.
> Each process updates different parts of the table.

Your ranges overlap. So one waits for the other on tuple=5001.

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Simon Riggs www.2ndQuadrant.com
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