[OSM-dev] OSM and sqlite

[Erik Johansson]

On Mon, Sep 29, 2008 at 9:59 PM, Igor Brejc <igor.brejc at gmail.com> wrote:
> Jochen Topf wrote:
>> On Mon, Sep 29, 2008 at 09:46:40PM +0200, Stefan Keller wrote:
>>
>>> db4o is also native .NET (but yeah, .NET *and* relational means that
>>> you are really on the dark side of the force :->).
>>>
>>> But Jochen could be right: I fear all embedded DBMS - whether
>>> relational or OO - are slow beyond some hundert MBytes.
>>>
>>
>> I meant slow because of Ruby, not because of Sqlite. Haven't benchmarked
>> sqlite.
>>
>> Jochen
>>
> I guess it also depends of what exactly you're trying to do with the
> data. I was thinking about using the DB for map rendering, which can be
> quite data- and processing-intensive.
> It looks like I'll have to test it myself when I get the chance and
> write something about it in the Wiki. Thanks for the info, guys.

I tried to use SQLite as a node+way  db while loading a 900MB
planet.osm it was *very* slow until I moved the node cache into a ram
disk (tmpfs). In memory caching doesn't scale to the whole planet, so
you have to write it to disk  and that was atleast 3-20 times slower
on import than mysql.. Then I have very slow laptop disks so hitting
disk is not something I like to do..

So yes it's slow, but I'm sure it's ok for desktop applications.