Skip to main content


Eclipse Community Forums
Forum Search:

Search      Help    Register    Login    Home
Home » Eclipse Projects » GEF » [GEF4] Possible memory leak in SelectionBehavior.updateHandles()
[GEF4] Possible memory leak in SelectionBehavior.updateHandles() [message #1734938] Mon, 13 June 2016 23:16 Go to next message
Colin Sharples is currently offline Colin SharplesFriend
Messages: 90
Registered: July 2009
Location: Wellington, New Zealand
Member

I'm seeing a memory leak in my GEF4 editor, which I think is related to SelectionBehavior.updateHandles().

In case it's not clear from my previous posts, my application is a map editor. The user can draw various terrain features like hills, rivers, roads, forests etc. Most of the terrain types store the model as a Path-like structure, i.e. a list of segments representing lines or curves. For example, a river will be composed of a list of cubic curves, which will be converted to a PolyBezier and rendered with a GeometryNode.

To draw a feature, the user selects the appropriate creation tool, then clicks on the waypoints of the feature, so you end up with a model object composed of a sequence of points, with control points in between to manage the curves. To edit a shape, the selection policy will create a selection handle at each waypoint, and another selection handle at each control point. Dragging the control point handle will change the shape of the curve.

In the control point's on drag policy, I call SelectionBehavior.updateHandles() after the operation is committed, so that the selection handles get updated with the new model locations. However, this seems to be causing a memory leak. I noticed that the application memory grows continuously as you add shapes, and much more rapidly than I would expect just from the model objects and parts.

Creating a large shape might involve a few hundred operations, so my first thought was that the operation history might be behind it. I made sure that the application clears the undo operation history on saving the application, but a save does not reduce the application's memory at all.

I had a look at the memory using the Eclipse Memory Analyzer, and the issue seems to be that the selection handle parts stick around in memory somewhere, I think AdaptableScope. The memory profile showed that AdaptableScope was responsible for about 53% of the heap size. The object counts also showed that there were tens of thousands of instances of my selection handle parts and their associated objects like StaticAnchor, when at the time I took the snapshot, the selected part had about 110 handles active.

Looking at SelectionBehavior.updateHandles(), I see that it calls AbstractBehavior.switchAdaptableScopes, so I am guessing that the problem is somewhere in there, although it may also be it the selection observer that removes and adds the feedback and handles when the selection changes. Any thoughts?


Colin Sharples
CTG Games Ltd
Wellington, New Zealand
Re: [GEF4] Possible memory leak in SelectionBehavior.updateHandles() [message #1734948 is a reply to message #1734938] Tue, 14 June 2016 04:54 Go to previous messageGo to next message
Alexander Nyssen is currently offline Alexander NyssenFriend
Messages: 235
Registered: July 2009
Location: L√ľnen
Senior Member
Off the top of my head I do not think that switching the adaptable scope is the problem. It simply ensures that newly created instances will be correctly scoped by Guice, but itself does not lead to the creation of instances.

I think we will have to investigate this in more detail (using a profiler). Can you please raise a bug?
Re: [GEF4] Possible memory leak in SelectionBehavior.updateHandles() [message #1735156 is a reply to message #1734948] Wed, 15 June 2016 23:08 Go to previous message
Colin Sharples is currently offline Colin SharplesFriend
Messages: 90
Registered: July 2009
Location: Wellington, New Zealand
Member

Opened #496227. I was able to demonstrate the same thing in the MVC Logo example - references to the selection handle parts remain in memory after the selection has changed.

Colin Sharples
CTG Games Ltd
Wellington, New Zealand
Previous Topic:[GEF4] DotEXport/DotImport subgraph
Next Topic:[GEF4] Calculation of stroke outline in model
Goto Forum:
  


Current Time: Fri Sep 21 07:32:21 GMT 2018

Powered by FUDForum. Page generated in 0.03474 seconds
.:: Contact :: Home ::.

Powered by: FUDforum 3.0.2.
Copyright ©2001-2010 FUDforum Bulletin Board Software

Back to the top