[PEAK] Re: [TransWarp] releasing component subtrees

[alexander smishlajev]

Phillip J. Eby wrote, at 21.10.2003 18:45:

>> our application from time to time is runnung tasks that should die 
>> after doing their job.  but my colleague found that the dead tasks 
>> remain in memory because of circular references between parent and 
>> child components that are not detected by python gc.
> 
> Python doesn't do GC on objects that have __del__ methods.  If you get 
> rid of the __del__ method in your example, the GC should run.

thank you.  it appears that nobody of our python programmers knew that.

> There's an easier way, at least for your example.  Declare your 'task1' 
> and 'task2' bindings as 'noCache=True'.

i am sorry, i cannot figure out how to use 'noCache'.  everything i try
in this example ends up with the same result: 'task1' and 'task2' stop
reporting their creation and run.

could you show an example of 'noCache' use?

>> below is a simple example.  it creates a task with two subtasks.  each 
>> of these tasks terminates as soon as it is run.  no reference is kept 
>> to the container task,
> 
> Not true; every component has a reference to its parent; that's how they 
> find their parents.

of course.  i meant that no reference is kept outside the subtree in
question.  sorry for being imprecise.

best wishes,
alex.