[OSM-dev] mod_tile / renderd issue

Wayne Walker wwalker at bybent.com
Tue May 13 15:03:53 BST 2008


Thank you.  I found that it was an improper path in mod_tile, just as
you expected.


On Tue, May 13, 2008 at 12:02:53AM +0100, Jon Burgess wrote:
> On Mon, 2008-05-12 at 08:57 -0500, Wayne Walker wrote:
> > Jon,
> > 
> > Thank you for the information.  Given that it is rendering and storing
> > in the .meta file,  How do I troubleshoot why it is not being served
> > from the .meta file (everytime I visit http://tiles/osm_tiles2/1/1/1.png,
> > renderd goes through rendering again)
> If you've got requests coming through from Apache into the renderd and
> it is producing .meta files then you're already 90% of the way there.
> I think you're strace approach is a good one but you need to do it on
> the Apache process to figure out why mod_tile can not access the .meta
> files. It will only request the tile to be rendered if it can not read
> it (or it thinks it is too old). It might be best to limit Apache to 1
> or 2 processes while debugging it
> If I had to take a wild guess I'd say that the problem is one of:-
> - Apache / mod_tile is failing to read the file due to a permission
> problem preventing access to the .meta files
> - Something like SELinux is blocking the file access (this often blocks
> the unix socket to the render daemon).
> - You've changed some of the settings in render_config.h but have not
> recompiled & installed mod_tile with these changes (and then restarted
> apache).
> - Perhaps you tried setting METATILE to something other than 8. I don't
> think I've tried any alternate settings recently. Things might break if
> you change it (especially if renderd and mod_tile have different
> settings).
> There are some debug statements in mod_tile which are commented out,
> search for ap_log_rerror in mod_tile.c. Most of these concern the input
> side of the request processing which you already seem to have working so
> I think these won't offer too much help.
> 	Jon


Wayne Walker

wwalker at bybent.com                    Do you use Linux?!
http://www.bybent.com                 Get Counted!  http://counter.li.org/
Perl - http://www.perl.org/           Perl User Groups - http://www.pm.org/
Jabber:  wwalker at jabber.bybent.com   AIM:     lwwalkerbybent
IRC:     wwalker on freenode.net

More information about the dev mailing list