[OSM-dev] osm2pgsql patch mode very slow.

[Steve Hill]

On Mon, 29 Sep 2008, Grant Slater wrote:

>> What are the postgres version requirements for patch mode?
>
>> = postgresql 8.2 with GIST and GIN index support compiled in.

Unfortunately I'm seeing the same problem after upgrading to 
the postgresql-8.3.4-1PGDG.rhel5 package.  The initial import of the 
planet goes ok with no errors, but it just hangs when importing the diffs:

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[mapnik at persephone osm2pgsql]$ ./osm2pgsql -m -d gis -a -s -C 500 
~/planet/20081001-20081002.osc.gz
osm2pgsql SVN version 0.55-20080813 $Rev: 9211 $

Using projection SRS 900913 (Spherical Mercator)
Setting up table: planet_osm_point
Setting up table: planet_osm_line
Setting up table: planet_osm_polygon
Setting up table: planet_osm_roads
Mid: pgsql, scale=100, cache=500MB, maxblocks=64001*8192
Setting up table: planet_osm_nodes
Setting up table: planet_osm_ways
Setting up table: planet_osm_rels

Reading in file: /home/mapnik/planet/20081001-20081002.osc.gz
-----

The load average is 1, but nothing seems to be using much CPU so I guess 
it's all I/O bound.  ps shows a number of postgres processes doing stuff:

-----
13459 ?        Ss     0:00 postgres: mapnik gis [local] idle in 
transaction
13460 ?        Ss     0:00 postgres: mapnik gis [local] COPY
13461 ?        Ss     0:00 postgres: mapnik gis [local] COPY
13462 ?        Ss     0:00 postgres: mapnik gis [local] COPY
13463 ?        Ss     0:00 postgres: mapnik gis [local] idle in 
transaction
13464 ?        Ds    20:28 postgres: mapnik gis [local] UPDATE
13465 ?        Ss     0:00 postgres: mapnik gis [local] idle in 
transaction
30097 ?        Ss     0:00 postgres: logger process
30099 ?        Ss     1:31 postgres: writer process
30100 ?        Ss     0:07 postgres: wal writer process
30101 ?        Ss     0:00 postgres: autovacuum launcher process
30102 ?        Ss     0:06 postgres: stats collector process
-----

  - Steve
    xmpp:steve at nexusuk.org   sip:steve at nexusuk.org   http://www.nexusuk.org/

      Servatis a periculum, servatis a maleficum - Whisper, Evanescence