On 02/11/2010 05:26 PM, Peter Körner wrote:
Note also that
osm.org doesn't use osm2pgsql for expiring tiles, they
have a custom script that doesn't look at relations. The reason for it
is that some edits to large relations can expire a lot of tiles IIRC.
I can't recall where the script is but it's some ruby script in OSM SVN.
Yes, i already adopted it for out multi-style-environment on cassini and
placed it at [1], but on cassini it was very slow with this much styles.
Do you know what the bottle neck was? Was it DB access to generate the
list of tiles, cpu speed running the ruby script, or filesystem
performance to touch a huge number of files? Presumably ptolemy is
running a different filesystem, so the latter might behave quite
differently. At first we can just touch the global planet-import
timestamp though every couple of days expiring all tiles at once while
we get everything else running reliably. I suspect there are still some
optimizations possible that might be sufficient, but we will need to see
what performance is like on ptolemy first.
Kai