[Geocoding] Maximum realistic performance (geocoded addresses per second)

[Mathias Versichele]

Ok, thanks for the info.

Mathias

On Fri, Mar 27, 2015 at 10:13 AM, Sarah Hoffmann <lonvia at denofr.de> wrote:

> On Fri, Mar 27, 2015 at 09:29:57AM +0100, Mathias Versichele wrote:
> > I see. Judging by the graphs, the server handles around 1000 successful
> > results per minute or almost 17 per second. Which is lower than what I am
> > seeing right now. Does that mean that I shouldn't expect any more gains?
>
> Not necessarily. The server is serving up to 8k reverse queries
> per minute at the same time. They are cheaper but still take time to
> process.
> Also, you need to add the search queries that yield 0 results. They are
> listed
> extra because in most cases they are more expensive (Nominatim needs to try
> more interpretations of the search query).
>
> If you look at it the other way around, a search query takes 250ms on
> average
> when the server is under full load. With 12 real CPUs and given that IO has
> very little influence because of the SSDs, I'd expect it can do easily
> 50 search queries per second. Naturally, that's all just
> back-of-the-envelope
> computation. And it's only a factor of 2. I suspect you can gain more by
> making sure your queries are well formed (adding commas between address
> parts, for example) and by reducing the database size to only the data
> you really need.
>
> Sarah
>
>
> > I understand the different factors influencing performance, but I'm more
> > trying to get a grasp of the maximum I should be aiming at (on a
> dedicated
> > system).
> >
> > On Fri, Mar 27, 2015 at 9:10 AM, Sarah Hoffmann <lonvia at denofr.de>
> wrote:
> >
> > > Hi,
> > >
> > > On Wed, Mar 25, 2015 at 10:56:30PM +0100, Mathias Versichele wrote:
> > > > using batch mode and experimenting with batch-size and the number of
> > > > simultaneous batch requests, my geocoding speed seems to level out at
> > > > around 25 addresses per second. Is it realistic to be still aiming
> for a
> > > > considerable improvement ? Without going through the details, are
> there
> > > any
> > > > kind of benchmarking results available (sort of like the planet
> imports).
> > >
> > > I'm not aware of any systematic benchmarking. You can have a look at
> the
> > > server stats for nominatim.osm.org at
> > >
> > >
> http://munin.osm.org/openstreetmap/pummelzacken.openstreetmap/index.html#nominatim
> > > to get an idea how that server is doing.
> > >
> > > Note that query speed can be vastly different depending on the
> hardware you
> > > have, what kind of area is imported and what kind of queries you have
> (even
> > > what kind of format your search term has can make a huge difference).
> So
> > > I'm
> > > not even sure benchmarks could have more than anecdotic value.
> > >
> > > Sarah
> > >
> >
> >
> >
> > --
> > Tel: +32 (09)/241.56.35
> > Mobile: +32 (0)485.16.07.08 <%2B32%20%280%29473.44.59.29>
> > www.geointelligence.be
> > <http://www.geointelligence.be/home-2/>
>



-- 
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