[Tilecache] Making TileCache seed faster?

[Christopher Schmidt]

On Thu, Apr 03, 2008 at 02:01:22PM -0600, Gregor Mosheh wrote:
> He's migrating from ka-Map to OL, and ka-Map, he observes, seems to be 
> faster at pregenerating tiles than TileCache. 

Is he using metatiles with one and not the other? (I think ka-Map
defaults to yes, tilecache defaults to no.) Note that TileCache will
report *tile* generation: if using metatiles, pre-caching means you're
actually getting a count that will be about 25 times slower than the
actual count because it only needs to fetch every 5th tile (in each
direction): so if you're using metaTiling, multiply by metaSize[x] *
metaSize[y] (default 5x5 -> 25) to get the *actual* speed.

> His question is whether 
> precache.php could be adapted to seed TileCache's cache, 

Probably.

> and whether it would be any faster.

No.

What version of TC are you using? Pre-1.9 used the remote service to
pre-cache: 1.9+ use local python for it. The former will be Very Slow if
the remote TileCache service uses CGI.

The pure act of 'precaching' is ~20 tiles/sec via CGI, 300 tiles/sec via
mod_python, and 10000 tiles/sec (essentially only limited by disk read
speed) via local Python.

Regards,
-- 
Christopher Schmidt
MetaCarta