See http://shootout.alioth.debian.org/gp4/benchmark.php?test=threadring&lang=all


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[jmn]
I tried the following, but it errors out with "can't create a new thread" - even though my system appears to have plenty of free memory.

Any ideas as to what limit I'm hitting? 

''[escargo] 4 Jun 2008'' - Well, how about telling us what version of Tcl and system you are using,
plus a description of its hardware resources?

[jmn] Tcl 8.5.2b1 - Vista x64 - core2 2.4Ghz 4G ram 

It seems to produce the error for ring_size >= 206

 - also, due to the above error, I haven't verified that the code below produces the right result. 
If anyone else runs it sucessfully, please make a note here as to whether it produces the expected result for N = 1000, of 498;  thanks.

[SL] It does return 498 for N = 1000. I can create up to ~800 threads. I guess to run this script in the same shell multiple time you have to release some threads.
 
======
 set ring_size 503
 set N 1000
 package require Thread
 proc done {} {
 	set ::done 1
 }
 set script {
 	proc accept {t} {
 		if {$t == 0} {
 			puts stdout "%i%"
 			thread::send -async %m% done
 			return
 		}
 		thread::send -async %n% [list accept [expr {$t - 1}] ]
 	}
 	%do%
 }
 set t1 [set tnext [thread::create {thread::wait}]]
 for {set i $ring_size} {$i >1} {incr i -1} {
  	set tnext [thread::create [string map [list %m% [thread::id] %i% $i %n% $tnext %do% "thread::wait"] $script]]
 }
 #close the ring
 set script [string map [list %m% [thread::id] %i% 1 %n% $tnext %do% [list accept $N]] $script]
 thread::send -async $t1 $script
 vwait ::done 
======

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!!!!!!
%| [Category Performance] |%
!!!!!!