[racket] thread size and creation time

Hi,

what is the reason that threads in Racket are so much bigger than in Gambit Scheme and take so much longer to create them? Is there possibly a way to come closer to Gambit performance or have threads in Gambit less functionality? In my little Racket test program below I get about 10kB per thread on my MacBook and creation takes about 100us per thread (Gambit claims to fit "millions of active threads in ~1GB and a creation time of 0.5us).

Marc Freely states in a talk from 2010 about Gambit http://www.iro.umontreal.ca/~gambit/Gambit-inside-out.pdf

Green threads
Preemptive scheduler with priorities
Very lightweight and scalable
Thread = descriptor (324 bytes) + continuation 
Thread creation/synchronization ~ 0.5 μs 
O(log N) enqueue/dequeue operations 
Supports millions of active threads (in ~ 1GB)


Best,
Berthold

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Berthold Bäuml -- Head of Autonomous Learning Robots Lab
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