Fixing GC error in Mac Common Lisp 5.0

Question

Hi all,

I'm fairly new to Lisp, and I'm trying to run an algorithmic music application on the original MCL 5.0 (not the RMCL version). The program works by incrementally inputting textual representations of music, and learning from the user via an association net. Unfortunately, shortly after I begin inputting the text, I begin to see the GC icon flash. The more text I input, the longer the GC will appear, until finally it will last so long that the application will crash. I've been talking with the creator of this application, and he's never had this problem. Any ideas as to how I might fix this? Perhaps somehow altering my MCL's GC preferences?

On a side note, when I input the text and the GC icon is flashing, in Activity Monitor it shows MCL using around 90% of my CPU's processing power, but not much RAM.

Thanks for the help,

Eddie

Answer 1

MCL on what OS and Mac?

It could be that MCL starts up with too little memory. Possible reasons: it is configured for too little memory, the Mac has too little free memory for some reason.

(room t)

shows details about the available memory.

It can also be that the program takes up too much memory when running. Reasons for that: it is not compiled or the available memory is too small.

Generally I would propose to use the MCL user mailing list for these questions.

Send a message with the text 'help' in the body to info-mcl-request @ digitool.com (remove the spaces). You will get a message how to subscribe. The actual mailing list is info-mcl @ digitool.com (again without the spaces).

Answer 2

Ah thank you for your help again. I will definitely join the MCL mailing list for future questions—I wasn't aware that such a thing existed.

I am running MCL on a 1.5 GHz Powerbook (G4 PPC) with 512MB RAM, on 10.4.11. I've reinstalled OSX so MCL is pretty much the only thing on the harddrive. The information I get when using the memory command (once I've loaded the music application) is that the total size of the Mac Heap is 1315K, with 20480K free; the Lisp Heap's total size is 18211K and has 8490K free. The Lisp Heap has used 9721K. I am pretty sure that the application has already been compiled. If you'd like to check it out yourself (it's an amazing program!) it is available at ftp://arts.ucsc.edu/public/cope/cmmc/Apprentice-Chapter11.sit

Best,

Eddie