Opened 14 years ago

Closed 14 years ago

Last modified 14 years ago

#772 closed defect (fixed)

[topology] ValidateTopology takes way too much time

Reported by: strk Owned by: strk
Priority: medium Milestone: PostGIS 2.0.0
Component: topology Version: master
Keywords: Cc:

Description

It's been running overnight (circa 7 hours now) w/out completing.

This is a topology with 33921 edges (total 314179 points), 26847 nodes and 12109 faces.

Haven't checked, but I bet it's the final checks for FACE/FACE overlap and FACE/FACE containment. There was a TODO in the code already about giving it more thoughts…

Change History (5)

comment:1 by strk, 14 years ago

Component: postgistopology
Owner: changed from pramsey to strk
Status: newassigned
Version: 1.5.Xtrunk

comment:2 by strk, 14 years ago

So, removing the check for overlapping faces and face-in-face makes the run complete in 7 minutes against a reduced topology which wasn't completing in over 6 hours.

This other, smaller topology has these characteristics:

  • 4896 nodes
  • 5687 edges (total 87222 points)postgis make collection
  • 1724 faces

Interesting enough, the validation reports lots of coincident nodes and an edge/edge crossing, which makes me wonder if it makes sense at all to try at analize faces if there are errors with edges (since faces are defined _by_ edges…)

comment:3 by strk, 14 years ago

Oh, wait… running the validation again takes 2.7 seconds !! I wonder if the first run was done before some kind of auto vacuum analyze !

Subsequent runs keep taking 2.7 secs..

comment:4 by strk, 14 years ago

Resolution: fixed
Status: assignedclosed

As of r6658 the smaller topology validation takes 26 seconds (while it used not to complete in an hour). Considering fixed for now.

comment:5 by strk, 14 years ago

Oh, the bigger topology just finished in 4 minutes and 15 seconds

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