[Tile-serving] Parallelizing more of osm2pgsql

[Paul Norman]

> From: Peter Körner [mailto:osm-lists at mazdermind.de]
> Sent: Thursday, July 18, 2013 2:40 AM
> Subject: Re: [Tile-serving] Parallelizing more of osm2pgsql
> 
> Hi
> 
> Am 17.07.2013 00:49, schrieb Paul Norman:
> > Something for discussion: Do we want to optimize non-slim mode or 
> > drop it? Right now it's slower and has a very high RAM requirement, 
> > so it really doesn't make sense to keep it as-is.
> 
> That's only true when talking about planet-imports. For small-area
> imports it can look very different here, couldn't it?

Although the increased RAM usage isn't an issue for small areas on most
hardware, I believe it's still slower than --slim --drop with appropriately
configure postgresql. My views are subject to modification if someone 
gets actual numbers on speed.

I'd suggest a benchmark with a smallish extract with the following cases

--slim --drop with parallized branch
--slim --drop with current master
Non-slim with either
If time permits, the first two with USE_TREE disabled