PARFOR Progress Monitor

A Java progress monitor to track progress through a PARFOR loop running MATLAB® workers

Description

A simple Java progress monitor to show a progress bar on the MATLAB client while Parallel Computing Toolbox workers are executing the iterations of a PARFOR loop. This employs a socket connection from the workers back to the MATLAB client to inform the client when an iteration has been executed.

The MATLAB code must be on the MATLAB path of both the client and the workers; additionally, the java classes must be added to the java class path using javaaddpath.

• MATLAB release: MATLAB 7.8 (R2009a)

[Stefan]

Nice idea, however it does not work for me. It works fine without matlabpool. With matlabpool it gives the following error within the parfor loop:

??? Error using ==> parallel_function at 594
Error in ==>
ParforProgMon>ParforProgMon.increment at 66
Attempt to reference field of non-structure
array.

Any ideas?

Kind regards,
Stefan

[Edric Ellis]

Hi Stefan,
Are you sure you've got the java code on the java path of the workers? I do something like this:
matlabpool local 3
addpath /path/to/stuff
pctRunOnAll javaaddpath /path/to/stuff

Cheers,
Edric.

[Stefan]

 

[Stefan]

Thank you for your help, now it works.
However, for large values of N (~50000) my Matlab crashes

java.net.SocketException: No buffer space available (maximum connections reached?): connect
at java.net.PlainSocketImpl.socketConnect(Native Method)
at java.net.PlainSocketImpl.doConnect(Unknown Source)
at java.net.PlainSocketImpl.connectToAddress(Unknown Source)
at java.net.PlainSocketImpl.connect(Unknown Source)
at java.net.SocksSocketImpl.connect(Unknown Source)
at java.net.Socket.connect(Unknown Source)
at java.net.Socket.connect(Unknown Source)
at java.net.Socket.<init>(Unknown Source)
at java.net.Socket.<init>(Unknown Source)
at ParforProgressMonitor$ProgWorker.increment(ParforProgressMonitor.java:30)

Best wishes,
Stefan

[Boris]

Thank you, very usefull!
I have a question though: is it possible to edit the progress bar in some way? In my case even the example won't fully display the word "example' in the upper bar.
It would be nice if the bar could adapt to what it should display or if the user could enter a length (character units?).

Best regards,
Boris

[Luke]

This is a great little program. However, i also get problems for large loops:

??? No method 'createServer' with matching signature found for class 'ParforProgressMonitor'.

Error in ==> ParforProgMon>ParforProgMon.ParforProgMon at 48
                o.JavaBit = ParforProgressMonitor.createServer( s, n );

[Alexandra]

This is a great tool, but it seems to delete all my global variables which is a bit annoying.
Also, I am of the same opinion as Boris. It is a bit small and I cannot read the full title. A few size options would be nice.

[Stephen]

To get this to work on osx, you need to modify the matlab class to append '.local' to the hostname.

 o.HostName = [cfg.hostname '.local'];