Re: Various intermittent bugs/instability - how to debug?

On Tue, Sep 09, 2008 at 04:50:53PM +0200, Frederik Ramm wrote:
> I have a rather large nightly process that imports a lot of data from
> the OpenStreetMap project into a PostGIS database, then proceeds doing
> all sorts of things - creating spatial indexes, computing bounding
> boxes, doing simplification of geometries, that kind of stuff. The whole
> job usually takes about five hours.

Which program is this?

> ERROR: invalid page header in block 166406 of relation "node_tags"

After this happens, can you find the relfilenode of the node_tags table
and extract the relevent block? Something like:

dd if=<dboid>/<relfilenode> bs=8k skip=166406 count=1 of=/tmp/block

What sort of data does it contain?

> ERROR: could not open segment 2 of relation 1663/24253056/24253895
> (target block 1421295656): No such file or directory

Does any file of that name exist?

ls 1663/24253056/24253895*

Hope this helps,
--
Martijn van Oosterhout <kleptog(at)svana(dot)org> http://svana.org/kleptog/
> Please line up in a tree and maintain the heap invariant while
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