Could you email me the command and I will try to break uDig as you have.
Jesse
On 8-Dec-06, at 12:38 AM, Schneider, Michael wrote:
Thank you, Jesse, for your work and the informations. That might be
a hint for me to have a closer look at.
When I detected the problem first, I was not using uDIG as an RCP
application but was using parts (plugins) of uDIG (seen from the
user's point of view only the map editor and the layers view) in
another RPC application.
But I repeated what I did with the "whole uDIG" as an RPC
application, and I could reproduce the error. Doing so I created a
command which added the layers (before it removed the old ones).
This was started from within Eclipse with no special settings set
(except those being part of the uDIG SDK). A plugin with this
command was the only enhancement to uDIG. I'm running on Windows XP
Professional.
Cheers,
Michael
Von: [EMAIL PROTECTED] [mailto:udig-devel-
[EMAIL PROTECTED] Im Auftrag von Jesse Eichar
Gesendet: Donnerstag, 7. Dezember 2006 23:44
An: User-friendly Desktop Internet GIS
Betreff: Re: AW: AW: [udig-devel] Heap space error adding/removing
graphicallayers
I have spent a good portion of today profiling uDig and found
something strange. As one adds and remove layers the Heap Size
keeps growing and growing and growing. However if the garbage
collector is ran the heap size goes right back down. It seems that
it is the byte arrays in the BufferedImages that are taking a while
to clear up. Perhaps if I pool them better rather than always
recreating them it will help the heap problem. But it seems to me
that the Garbage collector should kick in before a heap space error
occurs. ( I haven't been able to reproduce the heap space error
yet... I've added and removed 10 shapefile layers probably 30
times without problems. And I have the heap space set to the
default Java size.
I have tested on both windows and OSX. I did the profiling on OSX
but the performance seemed even better on Windows (shock!).
What is your configuration? Are there any other variable that I
can look at?
Jesse
On 7-Dec-06, at 6:05 AM, Jesse Eichar wrote:
Thanks Michael, I will look in to the problem and will get back
to you this evening on what I found.
Jesse
On 7-Dec-06, at 12:26 AM, Schneider, Michael wrote:
Jesse, thanks for the answers.
Sure, it's better to use one large shapefile instead of several
smaller ones. I tried that after detecting the heap space problem
with the gif files.
I think it is not the maximal amount of memory which causes the
problem, but perhaps a memory leak or memory fragmentation: Even
when adding and removing only one single layer I detect that
problem after having added and removed a layer more than 30 times.
Michael
Von: [EMAIL PROTECTED] [mailto:udig-devel-
[EMAIL PROTECTED] Im Auftrag von Jesse Eichar
Gesendet: Mittwoch, 6. Dezember 2006 18:13
An: User-friendly Desktop Internet GIS
Betreff: Re: AW: [udig-devel] Heap space error adding/removing
graphical layers
Hi,
There is a limitation to the number of layers that can be
realistically added because currently each layer has a buffer
that it writes to that is the size of the screen and is in 32-bit
colour. Obviously a good chunk of memory especially when the
screen is large. So it is better to have large shapefiles than
many shapefiles because the Shapefile renderer is highly
optimized for large shapefiles and performance will be much
better rendering a 1 GB shapefile than 100 100KB shapefiles.
This decision was part of the design because it allows some fun
optimizations (for example enabling and disabling layers) but as
of 1.1.1 we will have an "intelligent" system that will set a
maximum number of buffers depending on the memory size so that
this issue will no longer be a problem.
Jesse
On 6-Dec-06, at 3:54 AM, Schneider, Michael wrote:
Is grid coverage also involved when the layers are created from
shapefiles?
Using a bunch of shapefile layers instead of the GIF layers I
also ran into the same heap space error after adding and
removing the layers several times. (Each shapefile only had one
single feature, a point in this case.)
Michael
Von: [EMAIL PROTECTED] [mailto:udig-devel-
[EMAIL PROTECTED] Im Auftrag von Jesse Eichar
Gesendet: Dienstag, 5. Dezember 2006 18:47
An: User-friendly Desktop Internet GIS
Betreff: Re: [udig-devel] Heap space error adding/removing
graphical layers
Hi
There are 2 main possibilities that I can think of.
1. Make sure that you are passing in a heap space parameter to
your application or increase it if you already are. For example
-Xmx512M will assign 512 MB of memory to the heap space of the
JVM. That should help with the problem.
2. GridCoverage support is less than perfect at the moment
(although Jody is playing with a new version that shows promise)
and takes much more memory than it should. So it is likely that
the World+Image is what is causing problems. I'm not totally
sure what can be done about this. But if it is causing problems
then perhaps some memory optimizations can be made.
Jesse
On 5-Dec-06, at 3:33 AM, Schneider, Michael wrote:
Hello,
using uDIG RC 5 I got a heap space error after adding several
layers. Each layer was created from a very small graphic (png
or gif file of less than 1 KB) together with a world file. The
same was true when each layer was created from a small shapefile.
The intension is as follows: The user creates a list of
locations and these locations are shown on a map. When creating
a new list of locations, the old locations are removed from the
map and the new ones are displayed.
I did it similar to the descriptions in the FAQ "How do I
create a map programmatically" and "I want to add an image to
the map, how do I do that?"
I created a map using createCreateMapCommand
I added about ten layers (see above what the layers looked
like) with either createAddManyLayersCommand (all layers
together) or createAddLayerCommand (one layer at a time)
When a new list was created I removed the old layers using
createDeleteLayer command, set the new bounding box with
createSetViewportBBoxCommand and added the new layers to the map.
After doing these several times I run into the heap space error.
I also get this error when I only add and remove one layer
(i.e. location lists with only one entry), but it takes longer
to get the error.
I also tried it "the old way" with MapFactory.processURLs -
with a similar result: The error appeared as well, but it took
longer to get it.
Am I doing it the wrong way? Is there a better way?
I also wanted to try RC 6a. Are there any changes related to
the layers view and showing the map? In RC 5 after adding the
layer to the map they were displayed at once. In RC 6a I can
see them in the catalog and in the project window, but they do
not appear in the layers view automatically and are not
displayed. I'll have a closer look to that to see whether I get
the heap space error in RC 6a as well.
Michael
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User-friendly Desktop Internet GIS (uDig)
http://udig.refractions.net
http://lists.refractions.net/mailman/listinfo/udig-devel
_______________________________________________
User-friendly Desktop Internet GIS (uDig)
http://udig.refractions.net
http://lists.refractions.net/mailman/listinfo/udig-devel
_______________________________________________
User-friendly Desktop Internet GIS (uDig)
http://udig.refractions.net
http://lists.refractions.net/mailman/listinfo/udig-devel
_______________________________________________
User-friendly Desktop Internet GIS (uDig)
http://udig.refractions.net
http://lists.refractions.net/mailman/listinfo/udig-devel
_______________________________________________
User-friendly Desktop Internet GIS (uDig)
http://udig.refractions.net
http://lists.refractions.net/mailman/listinfo/udig-devel
_______________________________________________
User-friendly Desktop Internet GIS (uDig)
http://udig.refractions.net
http://lists.refractions.net/mailman/listinfo/udig-devel
