qgis - How do I compute v.kernel maps in less than 16 hours?

I am using the GRASS GIS 6.4.2 bundled with QGIS 1.8.0, using a PostGIS dataset exported via v.in.org.qgis from QGIS, to create kernel density maps.

The layer has 738,288 points.

My problem is the kernel density map takes about 16 hours to compute.

Here's parameters reported by v.kernel as it's executing:

STDDEV: 1000.000000
RES: 111.419043 ROWS: 458   COLS: 447

Writing output raster map using smooth parameter=1000.000000.

Normalising factor=6482635.018778.

I am running this on a Windows 7 x64 laptop with 8 GB RAM and an Intel Core i7 Q720 1.6 GHz with 4 physical cores. I notice that it's not multithreaded, only using 1 core.

Is there any way to speed this up without harming the quality of the output?

Answer

For the record, v.kernel has been improved in GRASS 7 the other day and takes (I believe) now less than 50% of the time.