[OSGeo Africa] QGIS/GRASS processing issue

[Chucker one]

Hi all,

I am trying to vectorize a 25Mb tiff file in QGIS using the GRASS r.to.vect
function in the processing toolbox. The data in the tiff file represents
water bodies and ranges from 0 to 2 (integer). The reason for using the
r.to.vect function is because it has a smoothing option.

The problem I have is it takes exceptionally long (24 hours +) to process
and freezes as soon as the "completed" message appears in the Log window.
This happens every time I run the process. I have also left the machine
overnight in the hope it recovers but with no success.

I am using QGIS 2.8 and have tried it on an Imac (3.4ghz, 16 Gb ram, 500Gb
ssd) and a windows machine (3.4Ghz 12 core, with 64Gb ram, 1Tb ssd). Both
machines have the same issue.

I would appreciate any input on why the above mentioned happens and how to
improve the processing performance/stability of QGIS.

Regards

Christian Smit
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