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

[M Josenhans]

Hi,

 > Some database stats are already there at
 > http://www.openstreetmap.org/wiki/index.php/Stats
I am afraid this is too much of data to be useful. :-)

It might even be worth to setup an application, which queries a certain 
set of data from the server, measures the response time and draws some 
graphs. In the end it is most important to measure the performance the 
way the users experience it.

Other statistics might be:
- number of accesses per hour
- response time in relation to the number of accesses per hour

Cheers,
Michael






Immanuel Scholz wrote:
> 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.