CPU scaling benchmark
workers
1 +1 main
iters total
500M
250000000/stream
elapsed
2186.85 ms
total CPU used
4328.15 ms
speedup
1.98×
vs serial
efficiency
99%
of 2× ideal
| stream | spawn ms | spawned@ | work start@ | work end@ | work ms | reap wait ms |
|---|---|---|---|---|---|---|
| 0 (main) | 0 | 2.05 | 2.06 | 2161.98 | 2159.92 | 0 |
| 1 | 2.008 | 2.03 | 15.78 | 2184.01 | 2168.23 | 22.16 |
main
w1
fork+handshake
CPU work
parent reap wait
what this measures
Each stream runs a tight integer LCG loop — working set is one CPU register, no memory access,
no shared data. Speedup = sum(stream CPU time) / wall-clock elapsed. Efficiency = speedup / (workers+1).
100% efficiency means perfect linear scaling; less than 100% is the cost of serial fork setup,
reap tail, SMT/core contention.