Superlab freezing


When I run my experiment, Superlab freezes after some trials.
Superlab doesn’t answer after that, and I have to restart the program.

I have a Mac OS X 10.4.11
867 MHz Power PC G4
640 Mb RAM
and 29 Gb free on the hard disk.

In my experiment I have about 50 trials and 400 events, the events are jpg images of 50Kb.

In the options of Superlab, I checked “load stimulus files for only one trial at a time”.

I need to add more RAM for that? or I have to do something else?

I would really appreciate any quick help for that, because I am testing subjects.

Hello Frédérique,

When you say SuperLab freezes, does press the Esc key to cancel an experiment still work?


Hi Hisham,

No, the Esc key doesn’t work.

Frédérique, can you email me the experiment?


I ran the experiment but wasn’t able to duplicate a crash. What did you increase RAM to? Your experiment is sizable; I don’t think 640 MB of RAM was enough. The only other noteworthy difference between your system and mine is that mine is an Intel-based MacBook.


I have now 1.12 Go RAM.

I tried my experiment on a new computer.
It’s a Mac OS X. 10.4.11. Dual 2 GHz Power PC G5. But there is just 512 MB RAM.
My experiment doesn’t work on this computer neither. With this computer, Superlab doesn’t freeze but stop my experiment and tell me this error messsage : “this file is not supported by the selected presenter : xxx.jpg”.

I will add at least 1 Go of RAM on this computer and try again my experiment.

Hi Frédérique,

Superlab doesn’t freeze but stop my experiment and tell me this error messsage : “this file is not supported by the selected presenter : xxx.jpg”.

Is it the same file every time? Can you preview it in SuperLab? I’m wondering if the problem is with that particular file (either something wrong with the file, or something special about it that SuperLab hadn’t anticipated).


No, it’s a different file each time I run the experiment, but I can preview them in Superlab.
Now, Superlab just run my two first events which are text but stop each time before presenting the first jpeg file.
I don’t know what to do with that.

Hi Hisham,

I remarked an interesting thing about the crash.
In fact, each time I start Superlab and I run my experiment for the first time, everything work well.
However, if I run the experiment a second time, Superlab stop my experiment at the half.
And if I try again, Superlab will stop my experiment before presenting my first picture.

And each time I try, Superlab does exactly the same pattern.

So, I can get round the problem, I just have to quit Superlab and restart it between each subject.

Can you tell me if this problem is due to Superlab or to my computer ?



Hi Frédérique,

This is probably due to a “memory leak” in SuperLab, i.e. memory being allocated but not necessarily freed after an experiment has ended. It takes exiting SuperLab completely to free the memory.

Thank you very much for the follow up post explaining that you narrowed down the problem. It’s very helpful to us. I’ve opened a case in our tracking system for this issue but I cannot promise a date.