[Pharo-project] garbage collection

[Chris Muller]

> Very strange. Shortly after I read your post I opened a unresponsive image
> myself. In the process stack I saw that magma was the culprit (didn't remember
> I have it installed in that image). However the problem was that I moved my
> directory and magma was looking for the old path. I didn't investigate further but
> it seems that the MagmaRepositoryController>>#open (called on startUp) is
> able to block the UI thread. In the same image I could use seaside still although
> the UI was frozen.

Hi.  Based on your description, it sounds like Magma hit its warning
condition check that it found a file named "_open" in the repository
directory, indicating it thinks another process has it open.  This can
occur if the server image did not shut down properly last time.

Before starting the image, see if there is a file called "_open" and,
if there is, delete it.  The image should start normally now.

This is something that has annoyed me at least a couple of times as
well.  I'm not sure what the UI process was doing in your case, but
Alt+. should allow you to interrupt it and see the stacks..  My
suspicion is that something in the image wanted a MagmaSession to do
something, but since the server was waiting for you to respond to the
Warning about "_open" it wouldn't return...

The confusing part for me is, the image startup code runs in the UI
process doesn't it?  So why were there two Processes to possibly get
into a deadlock?

 - Chris