[QGIS-Developer] Preview job and slow datasources

[Richard Duivenvoorde]

On 15-11-17 17:11, Matthias Kuhn wrote:

> Other factors that could be considered are things like how long it takes
> to cancel an ongoing rendering job or how many free connections we have
> in the pool.
> E.g. in the case of a WMST, the time to build the image might be high
> (as long as it's not coming from the cache) but it's worth preloading
> and showing in any case.

Is it possible that these preview-jobs are responsible for the WMTS
crashes which are reported in master (and I have myself pretty often)?

https://issues.qgis.org/issues/16966#change-84394

At least for WMST I would find retrieving 8 times the number of
images/requests too much? I pretty often have several WMS or WMST layers
in the a layerlist.

Regards,

Richard Duivenvoorde