[Tilesathome] Corrupted data in TRAPI database

[80n]

On Mon, Nov 30, 2009 at 6:12 PM, Andre Hinrichs <andre.hinrichs at gmx.de>wrote:

> Hi List!
>
> There seem to be corrupted data in the TRAPI database. Currently T at H has
> problems compiling tiles around Hawaii (e.g.
> http://tah.openstreetmap.org/Browse/details/tile/12/275/1818/).
> Rendering that tile throws a lot error messages like these:
>
> > Use of uninitialized value in multiplication (*) at
> /home/tilesathome/client-no-auto-1/osmarender/orp/orp-drawing.pm line 366.
> > Use of uninitialized value in numeric lt (<) at
> /home/tilesathome/client-no-auto-1/osmarender/orp/orp-drawing.pm line 403.
>
> but the rendering continues... Finally maplint crashes with the
> corrupted data:
>
> > Modification of non-creatable array value attempted, subscript -1 at
> /home/tilesathome/client-no-auto-1/osmarender/orp/orp-drawing.pm line 403.
>
> I ran T at H in debug mode for that tile and found that the downloaded file
> from API was only 1308 bytes of size whereas the downloaded data from
> TRAPI was 225051 bytes of size. Examing the TRAPI data I found that
> there are ways where some nodes are missing in the file (e.g.
> http://www.openstreetmap.org/browse/way/12222823). As you can see when
> you click on that link the way was deleted on 2009-11-23.
>
> Can someone please examine what went wrong? I assume that there was an
> error in the script updating the TRAPI database. As this should really
> never happen this error should be fixed ASAP.
>
> While the XAPI servers have not yet recent data I would suggest to let
> TRAPI online and try to find the error first. When the error is found
> and fixed (and XAPI servers have recent data) then TRAPI should possibly
> rebuild its database from scratch.
>
> Now that the minutely diffs are reliable I've started to think about the
possibility of each database mirror (TRAPI, ROMA, XAPI) publishing some kind
of checksum that provides a way of verifying that the database is complete.

A simple method would just be to publish a table containing the
minute-replicate sequence number and a count of nodes, ways and relations.

It would then be possible to compare these figures for each mirror and
immediately spot if any one was out of line with the others.

80n









> Regards
> Andre
>
>
>
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