Ticket #567 (closed enhancement: fixed)
v.kernel: suspected i/o bottleneck
|Reported by:||dylan||Owned by:||grass-dev@…|
v.kernel seems to have a disk i/o bottleneck, that starts to cause problems with moderately large input vector files. I use this command with <3000 point features, with a small region setting: approx 500x500 cells, regularly without issue. Trying out a larger dataset, 22k point features -- same region geometry, results in a lot of disk activity and very slow run-times. I took a peak at the source code, and it looks like there are several calls to a spatial index. There was some chatter on the mailing list a while back regarding improvement in the way that the spatial index is created. I wonder if this would improve v.kernel when working with a large number of features.
The reason that I suspect some kind of I/O issue -- I hear a lot of disk trashing while this module is running. Also note that it is using very little memory... perhaps some caching would speed things up.
Some details on the environment:
# region info: rows: 632 cols: 364 cells: 230048 # command and arguments # file 'soilweb_queries' has approx 22k records v.kernel --o in=soilweb_queries out=swq std=50000