Sync Channel Capacity Coordination Report

A capacity report records how a bounded channel handles offered messages. This program uses sync_channel with try_send and reports buffered versus rejected sends for the selected capacity.

Program

Play the program to choose the channel capacity and watch how many sends are buffered or rejected.

sync_channel_capacity_coordination_report.rs

use std::sync::mpsc::sync_channel;

fn main() {
    let capacity = ;
    let messages = 3;
    let (tx, _rx) = sync_channel(capacity);
    let mut sent = 0;
    let mut rejected = 0;
    for value in 0..messages {
        match tx.try_send(value) {
            Ok(()) => sent += 1,
            Err(_) => rejected += 1,
        }
    }
    let status = if rejected == 0 {
        "buffered"
    } else if sent == 0 {
        "saturated"
    } else {
        "partial"
    };
    println!("capacity={capacity} sent={sent} rejected={rejected} {status}");
}

use std::sync::mpsc::sync_channel;

fn main() {
    let capacity = ;
    let messages = 3;
    let (tx, _rx) = sync_channel(capacity);
    let mut sent = 0;
    let mut rejected = 0;
    for value in 0..messages {
        match tx.try_send(value) {
            Ok(()) => sent += 1,
            Err(_) => rejected += 1,
        }
    }
    let status = if rejected == 0 {
        "buffered"
    } else if sent == 0 {
        "saturated"
    } else {
        "partial"
    };
    println!("capacity={capacity} sent={sent} rejected={rejected} {status}");
}

use std::sync::mpsc::sync_channel;

fn main() {
    let capacity = ;
    let messages = 3;
    let (tx, _rx) = sync_channel(capacity);
    let mut sent = 0;
    let mut rejected = 0;
    for value in 0..messages {
        match tx.try_send(value) {
            Ok(()) => sent += 1,
            Err(_) => rejected += 1,
        }
    }
    let status = if rejected == 0 {
        "buffered"
    } else if sent == 0 {
        "saturated"
    } else {
        "partial"
    };
    println!("capacity={capacity} sent={sent} rejected={rejected} {status}");
}

bounded buffer `sync_channel` creates a bounded queue, so `try_send` reports `Ok` only while buffer space remains.

capacity report The selected capacity controls how many messages are buffered before `try_send` is rejected.

rendezvous A zero-capacity channel has no buffer, so every `try_send` without a waiting receiver is rejected and the report saturates.