I've some more questions: 1. is there a way to run "do-it"s and other user activity at a priority of 40, say, by default ? I know I can say "p := [ ... lenghty ...] forkAt: 40" and "p terminate" anytime in order to prevent user interface from freezing. 2. are my "forkAt:" processes supposed to appear in the Process Browser and if yes: where do I find them ? 3. If I open a workspace and a Transcript in a new (1.3-13315) image and run: p := [ 1 to: 10 do: [ :n | Transcript show: n; cr; cr; show: n factorial; cr; cr ]] forkAt: 40. then everything works fine. If I replace 10 by 1000 (don't do this yourself) then sometimes after a while the Transcript window turns red with two yellow lines and a debug window pops up with varying errors (mostly "subscript out of bounds"). Then again, in some cases it runs with no error. I have seen this in squeak 4.2, too. -- View this message in context: http://forum.world.st/process-priority-tp4092574p4092574.html Sent from the Pharo Smalltalk Users mailing list archive at Nabble.com.