[MapProxy] SQLite limits

[Oliver Tonnhofer]

On 04.11.2011, at 19:17, Fernando Ribeiro wrote:
> Currently my company holds about 2Tb of tiles (increasing) and we are evaluating upgrading our current tilecache based service, to mapproxy, preferably with mbtiles support.
> Our current major concern is the actual limit of an sqlite database, which is stated around 2Gb. If this is true, we would need a lot of partitioning...in other words, managing a lot of partitions, would be very annoying.

The file size limit of SQLite is 2TB and not 2 GB, but I'm not suggesting to use a single file. SQLite locks the whole database for all write operations. Adding a single tile is fast and should lock the file only for a few ms, but when you remove larger blocks of tiles, you need to do a vacuum and this will block the file for much longer. So, having smaller files is still advisable.

Partitioning would be done automatically by MapProxy (DB partitioning, not FS), but that is not yet implemented.

Regards,
Oliver

-- 
Oliver Tonnhofer    | Omniscale GmbH & Co KG    | http://omniscale.de
http://mapproxy.org | https://bitbucket.org/olt | @oltonn