[Tilesathome] Questions on tile updating process

[Maarten Deen]

Andre Hinrichs wrote:
> Hi List!
> 
> After two really nasty events (the TRAPI error a month ago and the server 
> crash a few days ago) the tiles are in a very bad state. Some tiles are very 
> old and some are completely empty whereas they shouldn't.
> 
> I have looked through the map and started rendering processes on many tiles 
> and little areas. But this is a uncongenial job since there are too many of 
> these bad tiles.
> 
> These days is a chance for rendering many things since there will be no render 
> processes from changed tiles...
> 
> 
> Questions:
> 
> 1.) Is there an automatism which can rerender these empty tiles? At least the 
> ones which are touching or left a coastline.
> 2.) Why can't I see when these empty tiles were beeing uploaded?
> 3.) I often see processes from petschge and LosHawlos which rerender old 
> tiles. Are these processes only for small areas? I'm asking because there are 
> sometimes tiles which are still very old and not beeing rerendered by these 
> processes. Example is (unless somebody renders it) tile with Zoom,x,y: (12, 
> 2396, 1164). Its date is 2008-09-18 which is exactly seven months today.

The only way I see for an external user is to load the details page for every 
tile (http://tah.openstreetmap.org/Browse/details/tile/12/x/y/) and get the 
"last modified" date.
But I don't think that would be very nice to the tah server.

I have always felt that there should be a process that enters the oldest tiles 
in the queue (with low priority) so that every tile will get rerendered with new 
rules every once in a while.

That said: there are still wrong rules or renderers that use out-of-date rules. 
I believe the issue of large names of waterfeatures and landfeatures in lower 
zoomlevels has surfaced before, but it is still an issue. See tile 12, 2111, 
1353 at 
<http://informationfreeway.org/?lat=51.957&lon=5.570&zoom=12&layers=B0000F000F>
where the text "Neder Rijn" (and "Lingekanaal" in a neigbouring tile) should not 
be there in zoom 12 and gets smaller in zoom 13 and 14 and gets larger again 
from zoom 15.
I have requested rerenders of other tiles to see if it is a current problem.

Regards,
Maarten