#567: v.kernel: suspected i/o bottleneck
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Reporter: dylan | Owner: grass-dev@lists.osgeo.org
Type: enhancement | Status: new
Priority: normal | Milestone: 6.5.0
Component: default | Version: svn-develbranch6
Keywords: v.kernel | Platform: Linux
Cpu: x86-32 |
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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
}}}