Re: Heap memory issues for Embedded Systems

[Klaus Ripke <paul-lua@...>]

On Tue, Jul 05, 2005 at 09:51:14PM +0100, David Given wrote:
> IIRC (and I possibly don't) you *cannot* run a hard realtime system with a 
> garbage collector. The problem is that there is no (short) upper limit on how 
> long it takes to do a garbage collection and since you can potentially run 
> out of memory at any point, your worst-case latencies are going to suck.
hum, guess GC need not be that unpredictable.
As "real time" always is about requests/events,
you clearly must not leave garbage from one request
lying yround to spoil the next one.
But when doing a full GC "after" every request (i.e. at the
end of the request, as far as total timing is concerned),
you should find a perfectly predictable environment for
every event, including the time it takes to clean up, no?

> *truly* hard real-time, with low latencies, I suspect you're doomed if you 
> use Lua.
recently I saw "realtime for Java" mentioned.
This is a joke, since java can not really control
it's GC due to MT issues.
But I guess Lua can.


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