[Openstreetmap-dev] Re: Ideas to lower server resources

[Immanuel Scholz]

Hi,

> I have no ruby profiling experience, however automatic collection of
> profiling data during normal operation in conjunction with  automatic
> generation of statistical performance graphs for different time
> intervals (hourly, daily, weekly, last week, etc.) helped in similar
> cases to achieve significant performance improvements over the time.
>
> Collecting this statistical data and having it automatically published
> on a web page, helps to determine changes (hw, sw, etc.) with negative
> performance impact and allows immediate correction those.

Cool. :-)

Some database stats are already there at
http://www.openstreetmap.org/wiki/index.php/Stats

My favourite list of (non ruby-intern) questions would be:
- How much resources (median) does one access to map.rb take?
- How much resources does one access to other url's take?
- How much resources does a tile-server request take?
- How many tile server requests do a typical request to a page have and
how many requests to map.rb? (and how many to other ruby scripts)

Resources are time *and* bandwidth. Both stats are relevant. (As example
it is worth almost nothing, if I optimize the map.rb script for bandwidth,
if it is <1% of the total, because the tile server has far more data to
transfer ;)

So the most relevant question is: Where are the bottlenecks? Or else: what
is the resource distribution to the components (tile server, map.rb, other
scripts)? Maybe there are other components to monitor later.

I think some or all of this could be extrakted from log files?


Ciao, Imi.