[gclist] Real-Time GC for high-level languages

Richard A. O'Keefe ok@atlas.otago.ac.nz
Wed, 31 Jan 2001 15:06:09 +1300 (NZDT)

Andrew Cheadle wrote:

    Apart from that I know that the Open-source Erlang provides only
    soft real-time behaviour.

Erlang's limitation to "soft real-time" doesn't really have a lot to do
with garbage collection.  Most garbage collections in Erlang are
thread-local.  The basic problem is Erlang IPC:
 - threads can communicate with threads on other nodes over a network,
   so there are unpredictable network delays
 - you can't tell the Erlang system everything it would need to know to
   do hard real-time scheduling.
I believe that the time to fully collect a thread is less than typical
LAN network delays.