[osmosis-dev] Improving completeWays/completeRelations performance

[Frederik Ramm]

Igor,

On 02/18/11 11:40, Igor Podolskiy wrote:
> just a random thought: what's wrong with using --dataset-bounding-box?
> Importing the planet file into a database and doing a bunch of queries
> against is equivalent to creating a single disk buffer for all bb tasks
> (the database _is_ the disk buffer, if you want). This still isn't very
> elegant as it requires two passes (import into DB and export to PBFs)
> but is IMHO more elegant than selection lists.

I currently use bounding polygons so I'd have to add a 
--dataset-bounding-polygon task for that but that should be possible.

The major problem is finding a database that would be able to import the 
data, index it, and fulfil my requests, all within less than 24 hours. 
 From what I hear, PostGIS takes a week for the import step alone but I 
want to produce fresh extracts every day. So I would have to import into 
PostGIS and then apply the daily diffs, but I could only do that if 
applying a daily diff and making all the bounding-polygon requests would 
take much less than a day and somehow I suspect that's not going to work.

> Don't get me wrong, maybe there's a reason why dataset tasks are
> unsuitable - but I've not found any... Maybe the dbb task itself needs
> improvement - but in this case, this should be the way to go.

I doubt that a performant solution can ever be found with PostGIS but 
I'd love to hear from someone who can prove me wrong.

Bye
Frederik