Re: ImageJ Plug-in - Extreme (10x) Execution Time Variability.

Posted by Stephan Saalfeld on May 04, 2011; 9:28pm
URL: http://imagej.273.s1.nabble.com/ImageJ-Plug-in-Extreme-10x-Execution-Time-Variability-tp3684711p3684712.html

Hi Rich,

try setting

-XX:MaxInlineSize=

to more than the default (35) and please report back if that has any
effect.  This JVM parameter sets the maximum bytecode size of a method
to be inlined.

http://www.oracle.com/technetwork/java/javase/tech/vmoptions-jsp-140102.html

Just for curiosity, what is the line doing that you have commented?

Good luck,
Stephan



On Wed, 2011-05-04 at 11:08 -0400, Richard VanMetter wrote:

> I have successfully written many plug-ins over the past few years. Being
> able to use ImageJ to demonstrate image processing concepts to clients
> has become a very valuable tool. Recently, I have encountered a very
> strange problem when executing an ImageJ plugin. It is without exception
> the strangest in 40 years of programming. Let me give some details:
>
> 1. the plug-in does interpolation and enlargement of an image as needed
> for implementation of the Burt & Adelson Laplacian-pyramid image
> encoding. The interpolation kernel is 5x5 and the enlargement is by a
> factor of two in both dimensions.
> 2. To apply the interpolation kernel, I divide the image into 9 regions;
> the four corners, the four sides and the center. For the corners and
> sides the interpolation is modified to accommodate the lack of data
> beyond the edges of the image. Thus, the program has 9 independent
> sections - one for each region of the image.
> 3. Section 9 treats the four pixels in the lower-right corner of the
> image. This section chooses among four slightly different methods
> depending on whether the enlarged (output) image is to have an even or
> odd number of rows and columns.
> 4. The problem has to do with the execution time for section 5 (the
> center region and by far the largest portion of the image). This section
> of the code finishes executing long before the code for section 9 is
> reached!
>      - if section 9 is omitted from the code, the execution time for
> section 5 of a 3001x3001 output image is ~ 600 ms
>      - if section 9 is present in the code, the execution time for
> section 5 is ~ 7000 ms or 7 seconds.
>      - I have isolated the behavior to certain lines if section 9.
>      - I can switch this time from 600 to 7000 ms repeatably by
> commenting and un-commenting as little as a single line of code in
> section 9.
>      - I have tried re-typing one of the 'offending' lines of code
> without solving the problem.
>
> When the problem was first encountered, I had been running JDK version
> 16 on my WindowsXP laptop. I upgraded to the latest Java Development
> Environment 1.6 version 25 without affecting the problem. Finally, I
> de-installed all Java runtime and development environments as well as
> ImageJ, followed by a fresh install of Download ImageJ 1.44 bundled with
> 32-bit Java 1.6.0_20 (28MB)from the ImageJ Download page. None of these
> actions have affected to above behavior...
>
> I also have done these tests on my older Linux (UBUNTU 10.4) desktop
> machine, running an older version of ImageJ (1.44i) with Java 1.6.0_05
> (32-bit) .... with very similar results. In this case, execution times
> were ~12.5 sec with the 'offending statements' and ~1.0 sec without.
>
> I am at my wits end.... Any suggestions would be greatly appreciated.
>
> Rich..