Re: Suggestion for concurrent index creation using a single full scan operation

On 2013-07-23 14:17:13 +0100, Greg Stark wrote:
> We already do this in pg_restore by starting multiple worker processes.
> Those processes should get the benefit of synchronised sequential scans.
>
> The way the api for indexes works y wouldn't really be hard to start
> multiple parallel index builds. I'm not sure how well the pg_restore thing
> works and sometimes the goal isn't to maximise the speed so starting
> multiple processes isn't always ideal. It might sometimes be interesting
> to be able to do it explicit in a single process.

That's true for normal index modifications, but for ambuild (the initial
index creation function) much less so. That's pretty much a black box
from the outside. It's possible to change that, but it's certainly not
trivial.

Greetings,

Andres Freund

--
Andres Freund http://www.2ndQuadrant.com/
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