v/vlib/sync/channel_polling_test.v

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1.2 KiB
V

// Channel Benchmark
//
// `nobj` integers are sent thru a channel with queue length`buflen`
// using `nsend` sender threads and `nrec` receiver threads.
//
// The receive threads add all received numbers and send them to the
// main thread where the total sum is compare to the expected value.
const (
nsend = 2
nrec = 2
buflen = 100
nobj = 10000
objs_per_thread = 5000
)
fn do_rec(ch chan int, resch chan i64, n int) {
mut sum := i64(0)
for _ in 0 .. n {
mut r := 0
for ch.try_pop(r) != .success {
}
sum += r
}
println(sum)
resch <- sum
}
fn do_send(ch chan int, start int, end int) {
for i in start .. end {
for ch.try_push(i) != .success {
}
}
}
fn test_channel_polling() {
ch := chan int{cap: buflen}
resch := chan i64{}
for _ in 0 .. nrec {
go do_rec(ch, resch, objs_per_thread)
}
mut n := nobj
for _ in 0 .. nsend {
end := n
n -= objs_per_thread
go do_send(ch, n, end)
}
mut sum := i64(0)
for _ in 0 .. nrec {
sum += <-resch
println('> running sum: $sum')
}
// use sum formula by Gauß to calculate the expected result
expected_sum := i64(nobj) * (nobj - 1) / 2
println('expected sum: $expected_sum | sum: $sum')
assert sum == expected_sum
}