CPU time very inaccurate on Windows 11
slaymaker1907 opened this issue · 0 comments
slaymaker1907 commented
On Windows 11 with an Intel 13900, the following causes incorrect reporting of CPU time:
(define (fibo n)
(if (> n 2)
(+ (fibo (sub1 n))
(fibo (- n 2)))
1))
(time (fibo 42))
One such execution gave me the output:
> (time (fibo 42))
(time (fibo 42))
no collections
0.453125000s elapsed cpu time
0.809243000s elapsed real time
0 bytes allocated
267914296
However, if I set affinity of the process to CPU 0 (locking it to one core), it correctly computes the CPU time.
> (time (fibo 42))
(time (fibo 42))
no collections
0.828125000s elapsed cpu time
0.855630300s elapsed real time
0 bytes allocated
267914296
I've tested this many times and have even seen this behavior on the non-threaded version.