[Qgis-developer] MTR and Postgis - lots of crashes

[Andreas Neumann]

Hi Denis,

Thanks for the hint.

I had a check on the nr of open connections on our PostgreSQL server.

The results of

SELECT sum(numbackends) FROM pg_stat_database;

are always in the 20ies.

I allow 100 connections on the PostgreSQL server. So this does not 
explain the problems.

The crashes always happen directly after project load. Once its loaded 
without a crash I never have subsequent crashes.

So something critical seems to happen on project load.

Andreas


On 06.11.2014 10:48, Denis Rouzaud wrote:
>
> On 06.11.2014 10:43, Andreas Neumann wrote:
>> Hi,
>>
>> Am I the only one that still gets a lot of crashes with complex 
>> projects when the data sources are on Postgis and MTR (parallel 
>> rendering in multiple cores) is turned on? I get most crashes on 
>> Windows, hardly any on Linux, but this may be due to the fact that 
>> Linux accesses Postgis locally, whereas the Win QGIS clients access 
>> Postgis remotely. Turning off MTR --> no more crashes.
>>
>> Is MTR and Postgis working flawlessly for everyone?
>>
>> These crashes really annoy me and I have to turn off MTR until these 
>> problems are fixed.
>>
>> Thank you for any hints / sharing your experiences with Postgis and MTR.
> I experienced freezes with MTR when I used joined attributes for 
> symbology/labelling. The joins being not cached.
> My interpretation was that the number of allowed connections to 
> postgres reached its maximum, and hence no connection is available to 
> fetch the layers used for labeling/symbology.
>
> Caching all my joins saved the problem on my side.
>
>
> I don't experience any trouble either on win or linux, and I suppose I 
> can say I have complex projects ;)
>
> Denis
>
>