Hello

The priorities in the threading system seem to behave somewhat strange (in beta21).

1. the default priority of the primordial thread is -1e10; is this on purpose and reasonable?

2. a thread with higher priority doesn't let other threads run at all, and this even if it calls yield. In the examples below, the lower-priority threads are only really started after higher priority ones have finished. Is this a feature or a bug?

Christian.

(prio 20000000 0 2 2e100)

baseprio cur before: #<thread #1 primordial> -1e10 baseprio cur after: #<thread #1 primordial> 0. baseprio before: #<thread #2> 0. baseprio before: #<thread #3> 0. baseprio after: #<thread #2> 2. baseprio after: #<thread #3> 2e100 started: #<thread #2> finished: #<thread #2> started: #<thread #3> finished: #<thread #3>

(prio 20000000 3 2 2e100)

baseprio cur before: #<thread #1 primordial> 0. baseprio cur after: #<thread #1 primordial> 3. baseprio before: #<thread #4> 3. baseprio before: #<thread #5> 3. baseprio after: #<thread #4> 2. baseprio after: #<thread #5> 2e100 started: #<thread #5> finished: #<thread #5> started: #<thread #4> finished: #<thread #4>

;; library function (supposed to format values like |error| does): (define warn (lambda l (if (pair? l) (let ((p (current-error-port))) (display (car l) p) (let loop ((l (cdr l))) (if (pair? l) (begin (write-char #\space p) (write (car l) p) (loop (cdr l))) (newline p)))) (error "warn called without arguments")))) ;; / library

(define (prio n cur p1 p2) (warn "baseprio cur before:" (current-thread) (thread-base-priority (current-thread))) (thread-base-priority-set! (current-thread) cur) (warn "baseprio cur after:" (current-thread) (thread-base-priority (current-thread))) (let ((proc (lambda () (warn "started: " (current-thread)) (let lp ((i n)) (if (positive? i) (begin (if (zero? (modulo i 1000)) (begin ;;(warn "thread-yield of:" (current-thread)) (thread-yield!))) (lp (- i 1))))) (warn "finished: " (current-thread))))) (let ((th1 (make-thread proc)) (th2 (make-thread proc))) (warn "baseprio before:" th1 (thread-base-priority th1)) (warn "baseprio before:" th2 (thread-base-priority th2))

(thread-base-priority-set! th1 p1) (thread-base-priority-set! th2 p2)

(warn "baseprio after:" th1 (thread-base-priority th1)) (warn "baseprio after:" th2 (thread-base-priority th2))

(thread-start! th1) (thread-start! th2)

(thread-sleep! 3);;(to make sure the thread-join!'s don't have an influence)

(values (thread-join! th1) (thread-join! th2)))))