mirror of
https://github.com/tokio-rs/tokio.git
synced 2026-08-18 00:00:09 +02:00
447 lines
12 KiB
Rust
447 lines
12 KiB
Rust
use callback::Callback;
|
|
use config::{Config, MAX_WORKERS};
|
|
use park::{BoxPark, BoxedPark, DefaultPark};
|
|
use shutdown::ShutdownTrigger;
|
|
use pool::{Pool, MAX_BACKUP};
|
|
use task::Queue;
|
|
use thread_pool::ThreadPool;
|
|
use worker::{self, Worker, WorkerId};
|
|
|
|
use std::error::Error;
|
|
use std::fmt;
|
|
use std::sync::Arc;
|
|
use std::time::Duration;
|
|
use std::cmp::max;
|
|
|
|
use num_cpus;
|
|
use tokio_executor::Enter;
|
|
use tokio_executor::park::Park;
|
|
|
|
/// Builds a thread pool with custom configuration values.
|
|
///
|
|
/// Methods can be chained in order to set the configuration values. The thread
|
|
/// pool is constructed by calling [`build`].
|
|
///
|
|
/// New instances of `Builder` are obtained via [`Builder::new`].
|
|
///
|
|
/// See function level documentation for details on the various configuration
|
|
/// settings.
|
|
///
|
|
/// [`build`]: #method.build
|
|
/// [`Builder::new`]: #method.new
|
|
///
|
|
/// # Examples
|
|
///
|
|
/// ```
|
|
/// # extern crate tokio_threadpool;
|
|
/// # extern crate futures;
|
|
/// # use tokio_threadpool::Builder;
|
|
/// use futures::future::{Future, lazy};
|
|
/// use std::time::Duration;
|
|
///
|
|
/// # pub fn main() {
|
|
/// let thread_pool = Builder::new()
|
|
/// .pool_size(4)
|
|
/// .keep_alive(Some(Duration::from_secs(30)))
|
|
/// .build();
|
|
///
|
|
/// thread_pool.spawn(lazy(|| {
|
|
/// println!("called from a worker thread");
|
|
/// Ok(())
|
|
/// }));
|
|
///
|
|
/// // Gracefully shutdown the threadpool
|
|
/// thread_pool.shutdown().wait().unwrap();
|
|
/// # }
|
|
/// ```
|
|
pub struct Builder {
|
|
/// Thread pool specific configuration values
|
|
config: Config,
|
|
|
|
/// Number of workers to spawn
|
|
pool_size: usize,
|
|
|
|
/// Maximum number of futures that can be in a blocking section
|
|
/// concurrently.
|
|
max_blocking: usize,
|
|
|
|
/// Generates the `Park` instances
|
|
new_park: Box<Fn(&WorkerId) -> BoxPark>,
|
|
}
|
|
|
|
impl Builder {
|
|
/// Returns a new thread pool builder initialized with default configuration
|
|
/// values.
|
|
///
|
|
/// Configuration methods can be chained on the return value.
|
|
///
|
|
/// # Examples
|
|
///
|
|
/// ```
|
|
/// # extern crate tokio_threadpool;
|
|
/// # extern crate futures;
|
|
/// # use tokio_threadpool::Builder;
|
|
/// use std::time::Duration;
|
|
///
|
|
/// # pub fn main() {
|
|
/// let thread_pool = Builder::new()
|
|
/// .pool_size(4)
|
|
/// .keep_alive(Some(Duration::from_secs(30)))
|
|
/// .build();
|
|
/// # }
|
|
/// ```
|
|
pub fn new() -> Builder {
|
|
let num_cpus = max(1, num_cpus::get());
|
|
|
|
let new_park = Box::new(|_: &WorkerId| {
|
|
Box::new(BoxedPark::new(DefaultPark::new()))
|
|
as BoxPark
|
|
});
|
|
|
|
Builder {
|
|
pool_size: num_cpus,
|
|
max_blocking: 100,
|
|
config: Config {
|
|
keep_alive: None,
|
|
name_prefix: None,
|
|
stack_size: None,
|
|
around_worker: None,
|
|
after_start: None,
|
|
before_stop: None,
|
|
},
|
|
new_park,
|
|
}
|
|
}
|
|
|
|
/// Set the maximum number of worker threads for the thread pool instance.
|
|
///
|
|
/// This must be a number between 1 and 32,768 though it is advised to keep
|
|
/// this value on the smaller side.
|
|
///
|
|
/// The default value is the number of cores available to the system.
|
|
///
|
|
/// # Examples
|
|
///
|
|
/// ```
|
|
/// # extern crate tokio_threadpool;
|
|
/// # extern crate futures;
|
|
/// # use tokio_threadpool::Builder;
|
|
///
|
|
/// # pub fn main() {
|
|
/// let thread_pool = Builder::new()
|
|
/// .pool_size(4)
|
|
/// .build();
|
|
/// # }
|
|
/// ```
|
|
pub fn pool_size(&mut self, val: usize) -> &mut Self {
|
|
assert!(val >= 1, "at least one thread required");
|
|
assert!(val <= MAX_WORKERS, "max value is {}", MAX_WORKERS);
|
|
|
|
self.pool_size = val;
|
|
self
|
|
}
|
|
|
|
/// Set the maximum number of concurrent blocking sections.
|
|
///
|
|
/// When the maximum concurrent `blocking` calls is reached, any further
|
|
/// calls to `blocking` will return `NotReady` and the task is notified once
|
|
/// previously in-flight calls to `blocking` return.
|
|
///
|
|
/// This must be a number between 1 and 32,768 though it is advised to keep
|
|
/// this value on the smaller side.
|
|
///
|
|
/// The default value is 100.
|
|
///
|
|
/// # Examples
|
|
///
|
|
/// ```
|
|
/// # extern crate tokio_threadpool;
|
|
/// # extern crate futures;
|
|
/// # use tokio_threadpool::Builder;
|
|
///
|
|
/// # pub fn main() {
|
|
/// let thread_pool = Builder::new()
|
|
/// .max_blocking(200)
|
|
/// .build();
|
|
/// # }
|
|
/// ```
|
|
pub fn max_blocking(&mut self, val: usize) -> &mut Self {
|
|
assert!(val <= MAX_BACKUP, "max value is {}", MAX_BACKUP);
|
|
self.max_blocking = val;
|
|
self
|
|
}
|
|
|
|
/// Set the thread keep alive duration
|
|
///
|
|
/// If set, a thread that has completed a `blocking` call will wait for up
|
|
/// to the specified duration to become a worker thread again. Once the
|
|
/// duration elapses, the thread will shutdown.
|
|
///
|
|
/// When the value is `None`, the thread will wait to become a worker
|
|
/// thread forever.
|
|
///
|
|
/// The default value is `None`.
|
|
///
|
|
/// # Examples
|
|
///
|
|
/// ```
|
|
/// # extern crate tokio_threadpool;
|
|
/// # extern crate futures;
|
|
/// # use tokio_threadpool::Builder;
|
|
/// use std::time::Duration;
|
|
///
|
|
/// # pub fn main() {
|
|
/// let thread_pool = Builder::new()
|
|
/// .keep_alive(Some(Duration::from_secs(30)))
|
|
/// .build();
|
|
/// # }
|
|
/// ```
|
|
pub fn keep_alive(&mut self, val: Option<Duration>) -> &mut Self {
|
|
self.config.keep_alive = val;
|
|
self
|
|
}
|
|
|
|
/// Set name prefix of threads spawned by the scheduler
|
|
///
|
|
/// Thread name prefix is used for generating thread names. For example, if
|
|
/// prefix is `my-pool-`, then threads in the pool will get names like
|
|
/// `my-pool-1` etc.
|
|
///
|
|
/// If this configuration is not set, then the thread will use the system
|
|
/// default naming scheme.
|
|
///
|
|
/// # Examples
|
|
///
|
|
/// ```
|
|
/// # extern crate tokio_threadpool;
|
|
/// # extern crate futures;
|
|
/// # use tokio_threadpool::Builder;
|
|
///
|
|
/// # pub fn main() {
|
|
/// let thread_pool = Builder::new()
|
|
/// .name_prefix("my-pool-")
|
|
/// .build();
|
|
/// # }
|
|
/// ```
|
|
pub fn name_prefix<S: Into<String>>(&mut self, val: S) -> &mut Self {
|
|
self.config.name_prefix = Some(val.into());
|
|
self
|
|
}
|
|
|
|
/// Set the stack size (in bytes) for worker threads.
|
|
///
|
|
/// The actual stack size may be greater than this value if the platform
|
|
/// specifies minimal stack size.
|
|
///
|
|
/// The default stack size for spawned threads is 2 MiB, though this
|
|
/// particular stack size is subject to change in the future.
|
|
///
|
|
/// # Examples
|
|
///
|
|
/// ```
|
|
/// # extern crate tokio_threadpool;
|
|
/// # extern crate futures;
|
|
/// # use tokio_threadpool::Builder;
|
|
///
|
|
/// # pub fn main() {
|
|
/// let thread_pool = Builder::new()
|
|
/// .stack_size(32 * 1024)
|
|
/// .build();
|
|
/// # }
|
|
/// ```
|
|
pub fn stack_size(&mut self, val: usize) -> &mut Self {
|
|
self.config.stack_size = Some(val);
|
|
self
|
|
}
|
|
|
|
/// Execute function `f` on each worker thread.
|
|
///
|
|
/// This function is provided a handle to the worker and is expected to call
|
|
/// [`Worker::run`], otherwise the worker thread will shutdown without doing
|
|
/// any work.
|
|
///
|
|
/// # Examples
|
|
///
|
|
/// ```
|
|
/// # extern crate tokio_threadpool;
|
|
/// # extern crate futures;
|
|
/// # use tokio_threadpool::Builder;
|
|
///
|
|
/// # pub fn main() {
|
|
/// let thread_pool = Builder::new()
|
|
/// .around_worker(|worker, _| {
|
|
/// println!("worker is starting up");
|
|
/// worker.run();
|
|
/// println!("worker is shutting down");
|
|
/// })
|
|
/// .build();
|
|
/// # }
|
|
/// ```
|
|
///
|
|
/// [`Worker::run`]: struct.Worker.html#method.run
|
|
pub fn around_worker<F>(&mut self, f: F) -> &mut Self
|
|
where F: Fn(&Worker, &mut Enter) + Send + Sync + 'static
|
|
{
|
|
self.config.around_worker = Some(Callback::new(f));
|
|
self
|
|
}
|
|
|
|
/// Execute function `f` after each thread is started but before it starts
|
|
/// doing work.
|
|
///
|
|
/// This is intended for bookkeeping and monitoring use cases.
|
|
///
|
|
/// # Examples
|
|
///
|
|
/// ```
|
|
/// # extern crate tokio_threadpool;
|
|
/// # extern crate futures;
|
|
/// # use tokio_threadpool::Builder;
|
|
///
|
|
/// # pub fn main() {
|
|
/// let thread_pool = Builder::new()
|
|
/// .after_start(|| {
|
|
/// println!("thread started");
|
|
/// })
|
|
/// .build();
|
|
/// # }
|
|
/// ```
|
|
pub fn after_start<F>(&mut self, f: F) -> &mut Self
|
|
where F: Fn() + Send + Sync + 'static
|
|
{
|
|
self.config.after_start = Some(Arc::new(f));
|
|
self
|
|
}
|
|
|
|
/// Execute function `f` before each thread stops.
|
|
///
|
|
/// This is intended for bookkeeping and monitoring use cases.
|
|
///
|
|
/// # Examples
|
|
///
|
|
/// ```
|
|
/// # extern crate tokio_threadpool;
|
|
/// # extern crate futures;
|
|
/// # use tokio_threadpool::Builder;
|
|
///
|
|
/// # pub fn main() {
|
|
/// let thread_pool = Builder::new()
|
|
/// .before_stop(|| {
|
|
/// println!("thread stopping");
|
|
/// })
|
|
/// .build();
|
|
/// # }
|
|
/// ```
|
|
pub fn before_stop<F>(&mut self, f: F) -> &mut Self
|
|
where F: Fn() + Send + Sync + 'static
|
|
{
|
|
self.config.before_stop = Some(Arc::new(f));
|
|
self
|
|
}
|
|
|
|
/// Customize the `park` instance used by each worker thread.
|
|
///
|
|
/// The provided closure `f` is called once per worker and returns a `Park`
|
|
/// instance that is used by the worker to put itself to sleep.
|
|
///
|
|
/// # Examples
|
|
///
|
|
/// ```
|
|
/// # extern crate tokio_threadpool;
|
|
/// # extern crate futures;
|
|
/// # use tokio_threadpool::Builder;
|
|
/// # fn decorate<F>(f: F) -> F { f }
|
|
///
|
|
/// # pub fn main() {
|
|
/// let thread_pool = Builder::new()
|
|
/// .custom_park(|_| {
|
|
/// use tokio_threadpool::park::DefaultPark;
|
|
///
|
|
/// // This is the default park type that the worker would use if we
|
|
/// // did not customize it.
|
|
/// let park = DefaultPark::new();
|
|
///
|
|
/// // Decorate the `park` instance, allowing us to customize work
|
|
/// // that happens when a worker thread goes to sleep.
|
|
/// decorate(park)
|
|
/// })
|
|
/// .build();
|
|
/// # }
|
|
/// ```
|
|
pub fn custom_park<F, P>(&mut self, f: F) -> &mut Self
|
|
where F: Fn(&WorkerId) -> P + 'static,
|
|
P: Park + Send + 'static,
|
|
P::Error: Error,
|
|
{
|
|
self.new_park = Box::new(move |id| {
|
|
Box::new(BoxedPark::new(f(id)))
|
|
});
|
|
|
|
self
|
|
}
|
|
|
|
/// Create the configured `ThreadPool`.
|
|
///
|
|
/// The returned `ThreadPool` instance is ready to spawn tasks.
|
|
///
|
|
/// # Examples
|
|
///
|
|
/// ```
|
|
/// # extern crate tokio_threadpool;
|
|
/// # extern crate futures;
|
|
/// # use tokio_threadpool::Builder;
|
|
///
|
|
/// # pub fn main() {
|
|
/// let thread_pool = Builder::new()
|
|
/// .build();
|
|
/// # }
|
|
/// ```
|
|
pub fn build(&self) -> ThreadPool {
|
|
trace!("build; num-workers={}", self.pool_size);
|
|
|
|
// Create the worker entry list
|
|
let workers: Arc<[worker::Entry]> = {
|
|
let mut workers = vec![];
|
|
|
|
for i in 0..self.pool_size {
|
|
let id = WorkerId::new(i);
|
|
let park = (self.new_park)(&id);
|
|
let unpark = park.unpark();
|
|
|
|
workers.push(worker::Entry::new(park, unpark));
|
|
}
|
|
|
|
workers.into()
|
|
};
|
|
|
|
let queue = Arc::new(Queue::new());
|
|
|
|
// Create a trigger that will clean up resources on shutdown.
|
|
//
|
|
// The `Pool` contains a weak reference to it, while `Worker`s and the `ThreadPool` contain
|
|
// strong references.
|
|
let trigger = Arc::new(ShutdownTrigger::new(workers.clone(), queue.clone()));
|
|
|
|
// Create the pool
|
|
let pool = Arc::new(Pool::new(
|
|
workers,
|
|
Arc::downgrade(&trigger),
|
|
self.max_blocking,
|
|
self.config.clone(),
|
|
queue,
|
|
));
|
|
|
|
ThreadPool::new2(pool, trigger)
|
|
}
|
|
}
|
|
|
|
impl fmt::Debug for Builder {
|
|
fn fmt(&self, fmt: &mut fmt::Formatter) -> fmt::Result {
|
|
fmt.debug_struct("Builder")
|
|
.field("config", &self.config)
|
|
.field("pool_size", &self.pool_size)
|
|
.field("new_park", &"Box<Fn() -> BoxPark>")
|
|
.finish()
|
|
}
|
|
}
|