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Review: Grid Engine Computing Video by Sun Java

Tuesday, June 5th, 2007 by def

Hi, I wrote a long review for this video, but can’t post it on youtube (500 character limitation).


Introduction to grid computing and the Grid Engine product with Fritz Ferstl and Miha Ahronovitz. Includes demo.

Please leave a comment on the video. Did you learn something? Were you bored? Do you want to see more?


My Review

I just watched the video and am giving some feedback.
Nice work guys.
Looks like you guys were going to talk to someone on the left in the beginning 🙂 But that’s just director issues. No problem.

The content:

Those examples Fritz gave made no sense in the beginning! Even for a scientist. “Generic dynamic service grids” (must have made this up on the fly), “globally connected resource pools” (makes some sense, but no.).

“boosting productivity, maximizing resource utilization, …blah blah” that all means nothing if you are trying to explain the thing.
“user focused on their core task” – sigh. What reading their emails? Browsing the web?
“decision support” – not in this talk.
“flexible and easy to use”, “time to market” – come’on, enough marketing spam.

OK, the purpose of the video?
– To educate people who know nothing about pc’s? This will never work at this level.
– For technically people? It’s too high level, I understand what a cluster is and that it has to be balanced (obviously).

This video makes the grid look like a game where you drag stuff around?

Is the grid engine a C or Java application that distributes itself to other computers (after setting up the SSH/RSH permissions to the other machines) in the grid specified in a config file of sorts? Or is it listening on a port for broadcast messages for machines running the grid client software?

Details people; otherwise this video helps no-one.

The idea is awesome though. Thanks.



Gimp script-fu gimp-drawable-set-pixel

Monday, April 2nd, 2007 by def

What’s this all about?

GIMP is a great free photo editing program. Like photoshop etc.
Script-fu is the name of the scripts that run in GIMP.
Scripts are written in the Scheme Language.

The problem

OK, this can be quite frustrating… the gimp-drawable-set-pixel function doesn’t seem to update the image in gimp!

The solution

Here’s the function you have to call to make your changes show and the script to work:


Credit to Saul Goode and Sven Neumann.

Step #1: Create a new image with a white background (any size will do)
and zoom in to the upper left corner.

Step #2: Open the Script-fu console (Xtns->Script Fu->) and enter the following commands
(the number “1” in the first line assumes the new image is the first one
created after opening the GIMP; substitute the appropriate image-IDnum
from the window’s titlebar if this is not the case):

(define image 1)
(define layer (car (gimp-image-get-active-layer image)))
(gimp-drawable-set-pixel layer 10 10 3 (cons-array 3 ‘byte))

Note that at this point, the pixel at location x=10, y=10 has “internally”
been painted BLACK (‘cons-array’ initializes to [0,0,0]) but the display
has not been updated.

Step #3: Enter the following line in the console:


Note that the display is not updated — this is somewhat anomalous (but
then Script-fu is not often used to paint on a pixel-by-pixel basis).

Step #4: The main undocumented step!

(gimp-drawable-update drawable startX startY lenghtX lengthY)

Hide and then unhide the layer by toggling its “eyeball” in the
Layers window. At this point the projection is updated to reflect that
the pixel at [1,1] has been painted black.

“It is amazing what you can accomplish if you do
not care who gets the credit.” — Harry S. Truman