[MapProxy] MBtiles locks & takes ages

[Oliver Tonnhofer]

Hi,


> On 22.10.2015, at 18:38, Tobias Wendorff <tobias.wendorff at tu-dortmund.de> wrote:
> I was about to preseed the area of Germany in OSM tiles and store them
> in sqlite databases (MBtiles). The log shows that the sqlite-DBs are
> locked every second. Isn't parallel processing possible with sqlite?
> 
> And the ETA also make problems. It would take about 2 weeks to render
> Germany. Even with the old python script in OSM's repository, I can
> render the data in some hours (png files only, no database). It's not
> a hardware problem.
> 
> Anyone with an idea, what's going wrong here?


A few users reported locking issues with SQLite, but the issue seem to be related to various system details as we are using SQLite caches without any issues.

Can you post the following details:

- Linux distribution and package versions (Kernel, Python, SQLite, MapProxy)
- Storage (local/remote, filesystem)
- MapProxy configuration
- Seeding configuration and options
- Speed of the seeding process when using the file cache (i.e. how many tiles does it write per second)
- Load of the system during seeding (load, %cpu and %wa output of top)

Please search the mailing list archive and GitHub issues for ‘sqlite’ and ‘locking’ for more information.


Regards,
Oliver

-- 
Oliver Tonnhofer  | Omniscale GmbH & Co KG  | http://omniscale.com
OpenStreetMap WMS and tile services         | http://maps.omniscale.com