Initial commit: Project structure, Coordinator Server v1.0.0, and Documentation

src/main.rs

@@ -0,0 +1,95 @@
+use bytes::{Bytes, BytesMut};
+use crossbeam_queue::ArrayQueue;
+use std::sync::Arc;
+use tokio::net::UdpSocket;
+use std::io;
+
+mod noise;
+
+/// Configuration for the data plane memory limits.
+const MAX_PACKET_SIZE: usize = 16384; // 16KB
+const PACKET_POOL_SIZE: usize = 10000; // ~160MB (10k * 16KB)
+const MAX_RAM_USAGE_MB: usize = 256;
+
+/// A fixed-size packet pool to prevent excessive allocations and fragmentation.
+struct PacketPool {
+    pool: Arc<ArrayQueue<BytesMut>>,
+}
+
+impl PacketPool {
+    fn new(capacity: usize, packet_size: usize) -> Self {
+        let queue = ArrayQueue::new(capacity);
+        for _ in 0..capacity {
+            let _ = queue.push(BytesMut::with_capacity(packet_size));
+        }
+        Self {
+            pool: Arc::new(queue),
+        }
+    }
+
+    /// Acquires a buffer from the pool or creates a new one if the pool is empty
+    /// (though in a strict memory-constrained environment, we might prefer to drop packets).
+    fn acquire(&self) -> BytesMut {
+        self.pool.pop().unwrap_or_else(|| BytesMut::with_capacity(MAX_PACKET_SIZE))
+    }
+
+    /// Returns a buffer to the pool for reuse.
+    fn release(&self, mut buf: BytesMut) {
+        buf.clear();
+        let _ = self.pool.push(buf);
+    }
+}
+
+struct DataPlane {
+    pool: Arc<PacketPool>,
+}
+
+impl DataPlane {
+    fn new() -> Self {
+        Self {
+            pool: Arc::new(PacketPool::new(PACKET_POOL_SIZE, MAX_PACKET_SIZE)),
+        }
+    }
+
+    async fn run(&self) -> io::Result<()> {
+        // Using current_thread runtime as specified for memory efficiency and avoiding cross-core synchronization overhead
+        let socket = UdpSocket::bind("0.0.0.0:0").await?;
+        println!("Data plane listening on {}", socket.local_addr()?);
+
+        loop {
+            let mut buf = self.pool.acquire();
+
+            // Zero-copy receiving: reading directly into the pooled buffer
+            match socket.recv_from(&mut buf).await {
+                Ok((len, addr)) => {
+                    // Use BytesMut::split_to to create a zero-copy 'Bytes' view for processing
+                    let packet = buf.split_to(len).freeze();
+
+                    // Simulate processing the packet without copying data
+                    self.process_packet(packet, addr).await;
+
+                    // Return the remaining buffer to the pool
+                    self.pool.release(buf);
+                }
+                Err(e) => {
+                    eprintln!("Error receiving packet: {}", e);
+                    self.pool.release(buf);
+                }
+            }
+        }
+    }
+
+    async fn process_packet(&self, packet: Bytes, addr: std::net::SocketAddr) {
+        // Logic for handling packets would go here.
+        // 'packet' is a reference-counted view into the original buffer.
+        let _ = packet.len();
+    }
+}
+
+#[tokio::main(flavor = "current_thread")]
+async fn main() -> io::Result<()> {
+    let dp = DataPlane::new();
+    println!("Starting memory-efficient data plane...");
+    println!("Estimated pool memory: {} MB", (PACKET_POOL_SIZE * MAX_PACKET_SIZE) / 1024 / 1024);
+    dp.run().await
+}