• Russ Cox's avatar
    runtime: parallelize garbage collector mark + sweep · d324f214
    Russ Cox authored
    Running test/garbage/parser.out.
    
    On a 4-core Lenovo X201s (Linux):
    31.12u 0.60s 31.74r 	 1 cpu, no atomics
    32.27u 0.58s 32.86r 	 1 cpu, atomic instructions
    33.04u 0.83s 27.47r 	 2 cpu
    
    On a 16-core Xeon (Linux):
    33.08u 0.65s 33.80r 	 1 cpu, no atomics
    34.87u 1.12s 29.60r 	 2 cpu
    36.00u 1.87s 28.43r 	 3 cpu
    36.46u 2.34s 27.10r 	 4 cpu
    38.28u 3.85s 26.92r 	 5 cpu
    37.72u 5.25s 26.73r	 6 cpu
    39.63u 7.11s 26.95r	 7 cpu
    39.67u 8.10s 26.68r	 8 cpu
    
    On a 2-core MacBook Pro Core 2 Duo 2.26 (circa 2009, MacBookPro5,5):
    39.43u 1.45s 41.27r 	 1 cpu, no atomics
    43.98u 2.95s 38.69r 	 2 cpu
    
    On a 2-core Mac Mini Core 2 Duo 1.83 (circa 2008; Macmini2,1):
    48.81u 2.12s 51.76r 	 1 cpu, no atomics
    57.15u 4.72s 51.54r 	 2 cpu
    
    The handoff algorithm is really only good for two cores.
    Beyond that we will need to so something more sophisticated,
    like have each core hand off to the next one, around a circle.
    Even so, the code is a good checkpoint; for now we'll limit the
    number of gc procs to at most 2.
    
    R=dvyukov
    CC=golang-dev
    https://golang.org/cl/4641082
    d324f214
print.c 5.59 KB