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use crate::execute_delay;
use crate::options::Options;
use crate::pretty::PrettyPrint;
use crate::PORT_COUNTERS;
use crate::REQUESTS;
use crate::REQUEST_BYTES;
use crate::RESPONSES;
use crate::RESPONSE_BYTES;
use anyhow::Result;
use futures::stream::{select_all, StreamExt};
use hyper::Response;
use owo_colors::OwoColorize;
use std::net::SocketAddr;
use std::sync::Arc;
use std::time::Duration;
use tracing::error;
use crate::create_listener;
use crate::ServerConfig;
pub fn run_thread(
id: usize,
addrs: Vec<SocketAddr>,
config: Arc<ServerConfig>,
opts: &Options,
) -> Result<()> {
// tokio io_uring implementation for Linux
use tracing::info;
let num_entries = opts.uring_entries.next_power_of_two();
let delay = opts.delay;
let mut uring = tokio_uring::uring_builder();
crate::configure_io_uring!(opts, uring);
let meter = opts.meter;
let verbose = opts.verbose;
tokio_uring::builder()
.entries(num_entries) // Large ring size is critical for throughput
.uring_builder(&uring)
.start(async move {
// Create multiple listeners for each address
let mut listeners = Vec::new();
for addr in &addrs {
let std_listener = match create_listener(*addr, opts) {
Ok(l) => l,
Err(e) => {
error!("Failed to create listener for {}: {}", addr, e);
return;
}
};
listeners.push(tokio_uring::net::TcpListener::from_std(std_listener));
}
info!(
"Thread {} listening on {:?} (tokio_uring, entries: {}, sqpoll: {:?})",
id, addrs, opts.uring_entries, opts.uring_sqpoll
);
// Convert each listener into a stream using unfold
let streams: Vec<_> = listeners
.into_iter()
.map(|listener| {
let port = listener.local_addr().unwrap().port();
Box::pin(futures::stream::unfold(listener, move |l| async move {
match l.accept().await {
Ok((tcp_stream, _)) => Some((Ok((tcp_stream, port)), l)),
Err(e) => {
error!("Accept error: {}", e);
// Continue accepting despite errors
Some((Err(e), l))
}
}
}))
})
.collect();
let mut all_listeners = select_all(streams);
loop {
match all_listeners.next().await {
Some(Ok((tcp_stream, port))) => {
let config = config.clone();
// Spawn task to handle the connection with io_uring
tokio_uring::spawn(async move {
if let Err(e) = handle_connection_uring(
tcp_stream, port, config, false, meter, delay, verbose,
)
.await
{
error!("Error handling tokio_uring connection: {}", e);
}
});
}
Some(Err(e)) => {
error!("Thread {} accept error: {}", id, e);
}
None => {
error!("Thread {} all listeners closed", id);
break;
}
}
}
});
Ok(())
}
#[cfg(all(target_os = "linux", feature = "tokio_uring"))]
async fn handle_connection_uring(
stream: tokio_uring::net::TcpStream,
port: u16,
config: Arc<ServerConfig>,
http2: bool,
meter: bool,
delay: Option<Duration>,
verbose: u8,
) -> Result<usize> {
use http_wire::WireDecode;
use std::mem::MaybeUninit;
use crate::response::build_response;
if http2 {
return Err(anyhow::anyhow!("HTTP/2 not supported with tokio_uring"));
}
let response_bytes = build_response(&config)?;
let mut response_buf = response_bytes; // Reuse to avoid allocations on each write
// Single buffer strategy for maximum performance:
// - In the common case (complete request in one read), we parse directly with zero copies
// - Only compact when we have leftover data from incomplete requests (rare case)
let mut buf: Vec<u8> = Vec::with_capacity(8192);
let mut parsed = 0; // Number of bytes already parsed/consumed
let mut requests_served = 0;
loop {
// FAST PATH: If we've consumed all data, reset the buffer (zero-cost operation)
if parsed == buf.len() && parsed > 0 {
unsafe {
buf.set_len(0);
}
parsed = 0;
}
// SLOW PATH: If we have many dead bytes at the beginning, compact the buffer
// This only happens when requests are split across multiple reads (rare)
else if parsed > 4096 {
buf.copy_within(parsed.., 0);
unsafe {
buf.set_len(buf.len() - parsed);
}
parsed = 0;
}
// Ensure we have enough spare capacity for reading
// Only reserve if needed to avoid unnecessary allocations in the common case
let current_len = buf.len();
if buf.capacity() - current_len < 4096 {
buf.reserve(4096);
}
// TRICK: Create a temporary Vec from the spare capacity for tokio_uring's ownership-based API
// This allows us to read directly into the buffer's unused capacity without copying.
// tokio_uring takes ownership of the buffer, passes it to io_uring, and returns it.
let spare_cap = buf.capacity() - current_len;
let temp_buf =
unsafe { Vec::from_raw_parts(buf.as_mut_ptr().add(current_len), 0, spare_cap) };
let (result, temp_buf) = stream.read(temp_buf).await;
std::mem::forget(temp_buf);
let n = match result {
Ok(0) => {
break; // Connection closed (EOF)
}
Ok(n) => n,
Err(e) => {
return Err(e.into());
}
};
// Update the main buffer's length and forget temp_buf to avoid double-free
// (temp_buf points to the same memory as buf's spare capacity)
unsafe {
buf.set_len(current_len + n);
}
// Parse all complete requests in the buffer
// This handles HTTP pipelining: multiple requests in a single read
let mut headers = [const { MaybeUninit::uninit() }; 128];
loop {
match http_wire::request::FullRequest::decode_uninit(&buf[parsed..], &mut headers) {
Ok((req, req_len)) => {
requests_served += 1;
parsed += req_len;
if verbose > 0 {
println!("↩ {}:\n{}", "request".bold(), req.pretty(verbose));
}
if meter {
REQUESTS.add(1);
REQUEST_BYTES.add(req_len);
let entry = PORT_COUNTERS.entry(port).or_default();
entry.requests.add(1);
entry.request_bytes.add(req_len);
}
if let Some(d) = delay {
execute_delay(d).await;
}
if verbose > 0 {
let mut print_builder = Response::builder().status(config.status);
for (k, v) in &config.headers {
print_builder = print_builder.header(k, v);
}
let print_resp = print_builder.body(config.body.clone()).unwrap();
println!("↪ {}:\n{}", "response".bold(), print_resp.pretty(verbose));
}
// Reuse response_buf (tokio_uring returns it after the write)
let (res, buf_back) = stream.write_all(response_buf).await;
response_buf = buf_back;
res?;
if meter {
RESPONSES.add(1);
RESPONSE_BYTES.add(response_buf.len());
let entry = PORT_COUNTERS.entry(port).or_default();
entry.responses.add(1);
entry.response_bytes.add(response_buf.len());
}
}
Err(_) => break, // Incomplete request or end of batch
}
}
// Loop continues: common case is parsed == buf.len(), so fast path activates on next iteration
}
Ok(requests_served)
}