Re: Parallel copy

On Thu, Apr 9, 2020 at 2:55 PM Andres Freund <andres@anarazel.de> wrote:
> I'm fairly certain that we do *not* want to distribute input data between processes on a single tuple basis. Probably
noteven below a few hundred kb. If there's any sort of natural clustering in the loaded data - extremely common, think
timestamps- splitting on a granular basis will make indexing much more expensive. And have a lot more contention. 

That's a fair point. I think the solution ought to be that once any
process starts finding line endings, it continues until it's grabbed
at least a certain amount of data for itself. Then it stops and lets
some other process grab a chunk of data.

Or are you are arguing that there should be only one process that's
allowed to find line endings for the entire duration of the load?

--
Robert Haas
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