How To Clear Java Heap Space Memory????

How to deal with "Java Heap Space Outofmemroyerror" seems to be a commonly asked question. I am using Matlab R2011a, and one solution is to increase the java Heap Size, which can be done at: File -> Preferences -> General -> Java Heap Memory.

My wondering is, is there any command like "clear STH " that can clear the Java Heap Space Memory, just like "clear all" clears the whole matlab workspace, so Java Heap Memory can always be freed when needed.

I thought "clear java" will do the trick. But it turns out "clear java" functions almost the same as "clear all", exept that it also clears all java classes... What i am looking for is something that will only clear memory of Java heap and preserve all other variables.

Anybody here knows how to do this trick?

Thanks.

[David Goldsmith]

I'm (newly) encountering the error in a DB query in an application which, ultimately, gets compiled--is there a "functional" way to execute the File->Preferences-> General-> Java Haap Memory sequence so that my compiled application can do it when necessary? Thanks!

[Patrik Ek]

I have also encountered this problem. Can it be concluded that this is no longer possible? Also are there any way to contact mathworks to contact mathworks directly on this issue. It seems that some updates or documentation are needed for this issue.

[Sunil]

Any solution ! facing same issue since 2010

Answer 1

[Jim Bosley]

This error kept me from publishing completed work. That is, Matlab did the analysis, but publish could not complete for the script.

I recently ran sbiofit. Got an answer. Plotted the results. Then I got an error in publishing the result, because of this issue.

I've tried reallocating more heap space. See https://www.mathworks.com/help/matlab/matlab_external/java-heap-memory-preferences.html . This did not work. A bummer, because Matlab completed the analysis, but couldn't publish the result in a pdf. FWIW, the heap size allocation is synopsized below: I hope that this works better for you all than for me.

Basically go to Environment tab and increase heap in Preferences > MATLAB > General > Java Heap Memory. Restart.

Error using evalmxdom>populateDom (line 246) Java exception occurred: java.lang.OutOfMemoryError: Java heap space

Error in evalmxdom (line 46) populateDom(dom,data,text,laste)

Error in publish

Error in mdbpublish (line 55) outputPath = publish(file, options);

Error using open (line 52) NAME must be a character vector or string scalar.

Answer 2

[Yair Altman]

Clearing Matlab's Java heap space has been long awaited, but I'm afraid that the suggested submission (Davide Tabarelli's JavaHeapCleaner) does nothing more than (1) clear the Swing (GUI) repaint buffer, and (2) run a Java garbage collection. This is just band-aid, that does not help with the basic problem of Matlab's internal memory leaks. It is not much more useful than the notorious pack command.

For those interested, this utility in replicated by the following short Matlab script, which does not require any download or JAR-file installation:

rm = javax.swing.RepaintManager.currentManager([]);
dim = rm.getDoubleBufferMaximumSize();
rm.setDoubleBufferMaximumSize(java.awt.Dimension(0,0));  % clear
rm.setDoubleBufferMaximumSize(dim);  %restore original dim
java.lang.System.gc();  % garbage-collect

Note: if your program does not use GUI, then only the last line is relevant for you: java.lang.System.gc()

I'm not disparaging this utility's attempt - I'm just saying that the core problem of memory leaks lies within Matlab's internals, and should be fixed by MathWorks.

Answer 3

[Jason]

I have this same problem. In earlier versions of Matlab 2010b etc, clear java just cleared the heap space as you suggested, but as of 2011a clear java clears just about everything. This change broke a bunch of my code. I look forward to a solution.

Answer 4

[Jakob Sievers]

I would like to join in the choir of people looking for a solution to this. Primarily to bump this thread back to the top of the discussion.

Cheers

Answer 5

[Arthur]

Seeing as how the question is still not answered I would to comment to get it back on top. I'm using matlab r2013a and I can't find a way to clear the java heap space.

cheers

Answer 6

[Karthik Vantakala]

Looking for a solution as well, bump!

Answer 7

[Andre Silva]

Also looking for an answer!

Answer 8

[Sunil]

Do we have any solution? I am struggling with this problem since 2010 !!

Answer 9

[Adam Neufeldt]

I also am looking for a solution

Answer 10

[Michael]

I use this (but I'm not sure it works on my mac--mavericks):

JavaHeapCL

Answer 11

[jessica grazziotin]

Same question!! Thank you.

Answer 12

[Jonathan]

years are passing on this one folks. hello? Mathworks please address this.

Answer 13

[Luke Perry]

I'm directly copying and pasting this onto a technical request. I just ran into this problem and there is no way around it.

Answer 14

[Jim Bosley]

jonathan wrote: "years are passing on this one folks. hello? Mathworks please address this."

I'm thinking that maybe eight years should be enough time to solve this? :)

Answer 15

[Luke Perry]

So the official response I recieved from Mathworks is to use this for now:

https://www.mathworks.com/matlabcentral/fileexchange/36757-java-heap-cleaner

And an enhancement request has been submitted to add this feature to a future MATLAB release.