[osmosis-dev] Inquiries about "Minutely Mapnik"

[Maxime Petazzoni]

Hi,

MapOSMatic, the free software web service to generate maps of cities
using OSM data, currently rely on a copy of the planet-wide PostGIS
database and we use the "traditional" way of keeping this database
up-to-date with the daily diffs and osm2pgsql.

Unfortunately, we're slowly getting to the point where, on our hardware,
applying this daily diff can take more than 24 hours, especially when
the server is under the load of map generation requests.

We are looking for solutions on how to solve this problem, and it seems
like reducing the delta of the updates to hourly increments (or even
minutely increments) with Osmosis + osm2pgsql could help. I indeed
expect applying a minute diff to be significantly fast, and that the sum
of these processings be smaller than what it would take for a daily
diff.

From your experience, can you confirm that this would be the case, and
that applying minute diffs won't take longer than a minute, or hourly
diffs longer than an hour (otherwise it would be impossible to stay
up-to-date with the database and we would start falling behind)?

The "Minutely Mapnik" wiki page on the OSM wiki
(http://wiki.openstreetmap.org/wiki/Minutely_Mapnik) seems to be a good
starting point to get this new technique of keeping our database updated
going. But I would like to try it first on my machine. Importing the
full planet.osm file would take forever though, so I'd like to try this
on a single country. Is it possible to use the osmosis replication data
on a subset of the planet?

Thank you in advance for your help,
- Maxime

-- 
Maxime Petazzoni <http://www.bulix.org>
 ``One by one, the penguins took away my sanity.''
Linux kernel and software developer at MontaVista Software
-------------- next part --------------
A non-text attachment was scrubbed...
Name: signature.asc
Type: application/pgp-signature
Size: 198 bytes
Desc: Digital signature
URL: <http://lists.openstreetmap.org/pipermail/osmosis-dev/attachments/20100526/8a5ed703/attachment.pgp>