[Geocoding] Nominatim performance

[Rodolphe Quiédeville]

Cambridge Cycling Campaign - Simon Nuttall <contact at camcycle.org.uk> writes:

> A whole world nominatim installation started on 2 Feb finished on 7
> Mar, and is now running at:
>
> http://nominatim.cyclestreets.net/
>
> It has entered the catch up phase - which began with data from 21 Jan.
>
> It seems to be taking a day to catch up with a day's updates - so it
> is not making much progress and is heavily i/o bound, even on a 32GB
> VM with 2 allocated processors.
>
> Do all these timings seem normal?
>
> What could I do to improve performance?

Hi,

As other says I think the main probleme here is your IO, if you can't
buy SSD try to split you database on multiple drives by using
tablespaces in postgres, one tablespace on one disk with tables and
another for indexes, it may helps.

I had the same problem recently but it was on hour update, and I
couldn't change the disks, an update took more than one hour. I've found
a solution for that, each hour I update the database without indexing by
using nominatim option --no-index, and twice a day I run update.php
without this option, this reduce a lot IO consumption. This was a
solution for me, hope this helps.

Regards,

-- 
Rodolphe Quiédeville - Expert Tsung
Consulting en performance des SI(G)
http://blog.rodolphe.quiedeville.org
Tel : 06 13 79 63 41