Replace unbounded with bounded as single channel is used

[ksolana]

We need the receiver to hold just one message so there is no need to have an unbounded channel.

[apfitzge]

Can you add a description to the PR so there's some record of what this does aside from code?

[apfitzge]

@ksolana Is there any affect on performance shown by benchmark from this change?

[ksolana]

@ksolana Is there any affect on performance shown by benchmark from this change?

Not really

base

running 6 tests
test bench_arc_mutex_poh_batched_hash            5,614,227.10 ns/iter (+/- 147,405.37)
test bench_arc_mutex_poh_hash                    5,748,522.90 ns/iter (+/- 118,654.13)
test bench_poh_hash                              5,577,250.00 ns/iter (+/- 90,381.88)
test bench_poh_lock_time_per_batch                  11,961.97 ns/iter (+/- 174.94)
test bench_poh_recorder_record_transaction_index     1,310.42 ns/iter (+/- 203.48)
test bench_poh_recorder_set_bank                 5,468,741.60 ns/iter (+/- 100.84)
test bench_poh_verify_ticks                     11,094,366.60 ns/iter (+/- 2,023,844.24)
test bench_poh_verify_transaction_entries       11,051,016.70 ns/iter (+/- 1,010,783.40)

diff

test bench_arc_mutex_poh_batched_hash            5,618,408.35 ns/iter (+/- 78,767.67)
test bench_arc_mutex_poh_hash                    5,761,056.30 ns/iter (+/- 1,493,131.64)
test bench_poh_hash                              5,604,585.40 ns/iter (+/- 81,242.69)
test bench_poh_lock_time_per_batch                  11,455.62 ns/iter (+/- 209.70)
test bench_poh_recorder_record_transaction_index     1,216.27 ns/iter (+/- 47.17)
test bench_poh_recorder_set_bank                 5,468,741.80 ns/iter (+/- 191.19)
test bench_poh_verify_ticks                     11,017,170.80 ns/iter (+/- 976,551.66)
test bench_poh_verify_transaction_entries       10,998,991.60 ns/iter (+/- 1,041,723.92)

[apfitzge]

Thanks, wouldn't expect a huge difference, if any. I think previously we would do:

1. create unbounded with no allocation
2. send call will allocate space for 1 element

Now we just

1. create bounded(1) with allocation for 1 element
2. send call just populates it