[OSM-dev] OSM Date Formats
Brett Henderson
brett at bretth.com
Mon Oct 15 23:37:06 BST 2007
Jon Burgess wrote:
> I've updated the planet.c code to generate dates in the format:
>
> 2007-07-10T11:32:32Z
>
> Loading a small planet dump in old vs new date format using Osmosis
> produces the following timings:
>
> OLD:
> real 12m44.875s
> user 2m4.975s
> sys 0m23.508s
>
> NEW:
> real 10m47.347s
> user 0m43.055s
> sys 0m2.443s
>
>
> A >50% drop in CPU utilisation by Osmosis, even more if you include the
> drop in system time as well. It is a shame that MySQL takes so long.
>
> Jon
>
Excellent, thanks for that.
As for MySQL, yes it's a big problem. Loading a full planet is
incredibly painful now. I'm open to suggestions on this one. The
MyISAM history tables are pretty fast, but the subsequent copying to the
InnoDB tables takes forever. I haven't timed it for 0.5 but 0.4 planet
was taking around 8 hours at last check. I've tried all sorts of things
to speed it up including dropping and re-creating indexes, none of it
seems to help much. I'm wondering if I should create a new task to
produce files that can be imported using the LOAD INFILE command but I
don't know if that will help.
More information about the dev
mailing list