Re: [9fans] Fun with libthread 1: The Sieve

[erik quanstrom <quanstro@coraid.com>]

> The program spawns n + 2 threads. sieve and counter are only spawned
> once, but filter is spawned for every prime number.
>
> With Roger's command line, primes took me about 91 seconds - possibly
> because it isn't looking for a specific end. primes 1 2837711 takes 43
> seconds.
>

perhaps roger is using a different version of primes.  the version
on sources finds all the primes before any are printed.  the output
is not buffered so that may also contribute quite a bit to the run
time.  (hence 1.25s of system time.)

	; time rc -c 'primes 1 10000000000 | sed 205963q | tail -5'
	2837629
	2837633
	2837677
	2837693
	2837711
	3.64u 1.25s 4.29r 	 rc -c primes 1 10000000000 | sed 205963q | tail -5  # status= rc 42288: primes 42289: sys: write on closed pipe pc=0x00005ef5||

i would imagine that pietro is running in an emulator to be 20x
slower.

but all this performance stuff misses the point.

- erik