On Wed, Sep 30, 2009 at 11:27 AM, Frank Broniewski <[email protected]> wrote: > I ask this question mainly because I found some oddities when examining the > diff process by osm2pgsql. Postgresql and Postgis are tuned according to the > oms wiki and Postgresql manual ... > First is a number of postgresql processes which are idle in transaction, this > usually means that there has been a transaction started with BEGIN but not > commited. Right now I have 5 processes of this kind and nobody else except > osm2pgsql is using the database right now. Maybe it is a flaw/problem in > osm2pgsql?
osm2pgsql has several copies running at once and unfortunatly you can only run one copy at a time per connection. So osm2pgsql opens a number of connections. As so yes, you get idle in transaction messages. This is normal. > At the start of the diff process I get errors in my postgresql log naming that > some _tmp tables do not exist and cannot be dropped: > > 2009-09-30 08:44:16 CEST ERROR: table "planet_osm_point_tmp" does not exist > 2009-09-30 08:44:16 CEST STATEMENT: DROP TABLE planet_osm_point_tmp; > 2009-09-30 08:44:16 CEST ERROR: table "planet_osm_line_tmp" does not exist > 2009-09-30 08:44:16 CEST STATEMENT: DROP TABLE planet_osm_line_tmp; > 2009-09-30 08:44:16 CEST ERROR: table "planet_osm_polygon_tmp" does not exist > 2009-09-30 08:44:16 CEST STATEMENT: DROP TABLE planet_osm_polygon_tmp; > 2009-09-30 08:44:16 CEST ERROR: table "planet_osm_roads_tmp" does not exist > 2009-09-30 08:44:16 CEST STATEMENT: DROP TABLE planet_osm_roads_tmp; Hmm, I forget the reason for those.... > osm2pgsql puts out some messages during import and I wonder what > storage efficiency: 11.34%, hit rate: 29.09% > mean. Maybe someone can shed some light onto this for me For efficiency osm2pgsql keeps a cache of nodes. Unfortunatly, this take more memory than most people have. What this means is that, in your cache, about 11% of the nodes fit in the cache, and that was good for 29% of node lookups. Bigger cache = higher hit rate = faster import. Have a nice day, -- Martijn van Oosterhout <[email protected]> http://svana.org/kleptog/ _______________________________________________ dev mailing list [email protected] http://lists.openstreetmap.org/listinfo/dev
