LC Garbage Collection?

[Tom Glod]

Dar, you bring up some good points here thanks.  i've been burned by that
before.

I do want to mention that I reported a bug a while back where not all
messages were sent while wait with messages.  panos seemed to have
confirmed that problem, but it hasn't moved since.

Maybe that part of the problem you experiences in your tests?

https://quality.livecode.com/show_bug.cgi?id=21835




On Tue, Sep 24, 2019 at 7:45 PM Dar Scott Consulting via use-livecode <
use-livecode at lists.runrev.com> wrote:

> Yeah, "GUI recursion" is a little obtuse.
>
> I'm referring to a style of using wait with messages inside an event
> handler so that other events (especially keyboard and mouse) can be
> handled. Sometimes this is done to allow a "background" task. It is easy to
> do this in a way that makes a mess of things. One scenario is loading a
> large file at the start of a mouseUp and then use lots of wait with
> messages sprinkled throughout, but the task somehow gets started several
> times and memory usage is a problem.
>
> Of course one can be very careful and consider what problems might happen,
> so this is not a hard and fast admonition. The use of busy flags can help.
>
> I do this occasionally when experimenting with move, but I move away
> immediately.
>
> And I do like the idea of writing a "background" the way one thinks of it
> and sprinkling in some waits, but as soon as things expand (you want to do
> two things in the background), then this falls apart.
>
> I encourage embracing event programming.
>
> > On Sep 24, 2019, at 2:43 PM, Tom Glod via use-livecode <
> use-livecode at lists.runrev.com> wrote:
> >
> > HH...yup I know...... Dar, thanks for those hints and tidbits, I'll be
> > putting those right into my pocket as i optimize code going forward.
> >
> > I have pretty good cleanup habits, so  I am getting good results with how
> > it is (in 9.05) ..... but sometimes its scary.  It like the GC happens
> only
> > when things are idle and quiet....maybe there is a threshold.
> >
> > When you say GUI recursion....do you mean,,,,if i draw interfaces using
> > functions that call themselves?
> >
> > On Tue, Sep 24, 2019 at 3:40 PM Dar Scott Consulting via use-livecode <
> > use-livecode at lists.runrev.com> wrote:
> >
> >> I don't know where you will find details. (Maybe if we keep this
> >> conversation going, we will get a response in a half day.)
> >>
> >> I believe it is reference-counting with lazy cleanup for high-level
> >> objects, but with carefully crafted destructors for low level objects.
> >> Because of the lazy cleanup, it is sometimes hard to see when memory
> >> problems occur or to infer GC behavior
> >>
> >> But, to me it doesn't matter. I like the memory management of LiveCode.
> It
> >> cleans up. It doesn't have astonishingly-long pauses that I remember. It
> >> would be nice to know that cleanup is not delayed forever, though, and
> for
> >> that I am not sure. I have only run into memory problems with some ML
> >> projects, so my experience might not shed much light.
> >>
> >> Sources of memory leaks are LC, LC scripts, OS, libraries, LCB and (I
> >> suppose) compilers. I don't think we can assume the problem is not in
> the
> >> user script. I have seen script memory leaks like these:
> >> 1. Leaving large data in script locals
> >> 2. Indefinite log variables
> >> 3. Poor range checking in recursive functions
> >> 4. mouseUp recursion*
> >> 5. Queue/stack bugs
> >> 6. Bad parsing
> >>
> >> *GUI recursion is a root of all kinds of evil. If tempted, leave your
> >> cloak and run.
> >>
> >> Dar Scott
> >> Mad Scientist
> >>
> >>> On Sep 24, 2019, at 12:36 PM, Tom Glod via use-livecode <
> >> use-livecode at lists.runrev.com> wrote:
> >>>
> >>> Hi folks, I'm wondering if anyone can help me to understand Livecode's
> >>> garbage collection.  I am developing an application that is intended to
> >>> stay in memory and so I must watch memory consumption carefully. I've
> had
> >>> some instances where memory ran way out of control.... but I found a
> >> couple
> >>> of reasons for that...... one of them being the dozen or so memory
> leaks
> >>> that were fixed in 9.05.
> >>>
> >>> When I build the standalone in 9.04 its a disaster. When I build with
> >> 9.05
> >>> I am very impressed with my application clearing its own memory.....
> even
> >>> to the point where it consumes less than what it does when the
> standalone
> >>> first starts up
> >>>
> >>> But it seems arbitrary.  Where can I go to find out more details about
> >> the
> >>> engine's GC?
> >>>
> >>> Thanks,
> >>>
> >>> Tom Glod
> >>> Founder & Developer
> >>> MakeShyft R.D.A (www.makeshyft.com)
> >>> Office:226-706-9339
> >>> Mobile:226-706-9793
> >>> _______________________________________________
> >>> use-livecode mailing list
> >>> use-livecode at lists.runrev.com
> >>> Please visit this url to subscribe, unsubscribe and manage your
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> >>
> >>
> >> _______________________________________________
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> >
> >
> > --
> > Tom Glod
> > Founder & Developer
> > MakeShyft R.D.A (www.makeshyft.com)
> > Office:226-706-9339
> > Mobile:226-706-9793
> > _______________________________________________
> > use-livecode mailing list
> > use-livecode at lists.runrev.com
> > Please visit this url to subscribe, unsubscribe and manage your
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>
>
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-- 
Tom Glod
Founder & Developer
MakeShyft R.D.A (www.makeshyft.com)
Office:226-706-9339
Mobile:226-706-9793