[Tilesathome] t at h server performance

[Rob Reid]

Christopher Schmidt wrote the following on 23/12/2007 03:43:
> Since low content tilesets may result
> in many hundreds of selects / "REPLACE INTO"s, this process is the
> primary slow part of the tileset processing. 
>   
Are you able to tell if there is much difference in processing time 
between a low content tileset where the blank tile info already in the 
database is just being verified/updated and a low content tileset for 
which the blank tile info is being inserted for the first time. Is the 
slowdown mostly happening when processing 'server:MissingTile' tilesets? 
I guess at some stage we may get to the point where missingTile requests 
should drop off? Is there any info available on what percentage of z12 
tilesets are now on the tah server, since the move from dev?     
> In the short term, making the processing take priority into account --
> so that higher priority tilesets are processed before lower priority
> tilesets -- seems important to me, since that's the thing that affects
> people the most. IF they have to wait 3 hours for all the low priority
> crap to clear through in order to see the tiles they just uploaded at
> priority 1, that's clearly a bad feedback loop.
>   
This seems like a great idea even if there was no slowdown. Since a  
priority 1 request will jump to the front of the pending queue for 
handing out to renderers it does not make much sense for them to 
possibly get stuck behind ~1500 priority 3 requests when they are being 
processed after uploading.
For the mapping I'm doing at the moment I try to render most of  the 
tilesets I'm changing myself and the wait after upload until the changes 
appear is the biggest delay for me most of the time.

Cheers

rcr