[Qgis-user] Project takes very long to load

Andreas Neumann a.neumann at carto.net
Fri Apr 24 01:53:36 PDT 2009


Hi Paolo,

Which email are you refering to?

This one?
http://lists.osgeo.org/pipermail/qgis-user/2009-April/005183.html

Here is what I did so far:
I saved the project as a different name. So far this did not speed things
up. I did a project file comparison in the OxygenXML editor. There are
only minor differences, like

<provider>postgres</provider>
changed to
<provider encoding="System">postgres</provider>

and in <patialrefsys>:

<geographicflag>true</geographic>
changed to
<geographicflag>false</geographic>

for some reasons I don't know.

I did not recreate the project so far. It is not very easy. I spent hours
of work to define the project's symbolization, including complex text
symbolization, SVG symbols, a lot of unique-value to point/line symbol
assignments, etc. It is not something I can redo in a couple minutes.

I have to mention that I use a lot of views, which are again using a lot
of table joins. However, all of my tables have primary keys (of PostgreSQL
type integer) and the views are registered in the public.geometry_columns
table.

Jürgen suggested to build a debug build - which I did today.

Here is what I observed from the debug output:

At least 90% or more of the time is spent parsing the table PostgreSQL
table definitions.

I get outputs like:
.* "?ww_utilisation_tbd"?\."?value"? AS "?(\w+)"?,* .*
.* "?ww_reinstatement_tbd"?\."?value"? AS "?(\w+)"?,* .*

Both are joined tables in a view definition. It takes approx. a second per
debug lines and there are at least 100-200 of these messages (I could not
count it).

As I said - I can make the data and project file available to selected
developers. I can't upload this to the general public as it contains all
of community's survey and waste-water data - which is not available for
free to the general public (unfortunately). However, if a developer has
the time to look into the issue, I can make a copy available.

As it looks like currently, Jürgen offered to help me on the issue.

Thanks,
Andreas


On Fri, April 24, 2009 9:51 am, Paolo Cavallini wrote:
> Andreas Neumann ha scritto:
>> I hope that we can find a solution - because in case I want to do a
>> presentation of QGIS I cannot afford to wait 3-4 minutes for the project
>> to start up. Also, I was planning to use this project as a quick viewing
>> and printing solution. If I cannot get it to load in 10-30 seconds I
>> won't get acceptance from my work colleagues.
>
> I wrote a few suggestions in an earlier mail: did you check?
> Please do and report the results.
> Thanks.
> --
> Paolo Cavallini: http://www.faunalia.it/pc
> _______________________________________________
> Qgis-user mailing list
> Qgis-user at lists.osgeo.org
> http://lists.osgeo.org/mailman/listinfo/qgis-user
>


-- 
Andreas Neumann
http://www.carto.net/neumann/
http://www.svgopen.org/




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