Files
tokio/src/runtime/builder.rs
T

369 lines
10 KiB
Rust

use runtime::{Inner, Runtime};
use reactor::Reactor;
use std::io;
use std::sync::Mutex;
use std::time::Duration;
use num_cpus;
use tokio_reactor;
use tokio_threadpool::Builder as ThreadPoolBuilder;
use tokio_timer::clock::{self, Clock};
use tokio_timer::timer::{self, Timer};
/// Builds Tokio Runtime with custom configuration values.
///
/// Methods can be chained in order to set the configuration values. The
/// Runtime 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;
/// extern crate tokio_timer;
///
/// use std::time::Duration;
///
/// use tokio::runtime::Builder;
/// use tokio_timer::clock::Clock;
///
/// fn main() {
/// // build Runtime
/// let mut runtime = Builder::new()
/// .blocking_threads(4)
/// .clock(Clock::system())
/// .core_threads(4)
/// .keep_alive(Some(Duration::from_secs(60)))
/// .name_prefix("my-custom-name-")
/// .stack_size(3 * 1024 * 1024)
/// .build()
/// .unwrap();
///
/// // use runtime ...
/// }
/// ```
#[derive(Debug)]
pub struct Builder {
/// Thread pool specific builder
threadpool_builder: ThreadPoolBuilder,
/// The number of worker threads
core_threads: usize,
/// The clock to use
clock: Clock,
}
impl Builder {
/// Returns a new runtime builder initialized with default configuration
/// values.
///
/// Configuration methods can be chained on the return value.
pub fn new() -> Builder {
let core_threads = num_cpus::get().max(1);
let mut threadpool_builder = ThreadPoolBuilder::new();
threadpool_builder.name_prefix("tokio-runtime-worker-");
threadpool_builder.pool_size(core_threads);
Builder {
threadpool_builder,
core_threads,
clock: Clock::new(),
}
}
/// Set the `Clock` instance that will be used by the runtime.
pub fn clock(&mut self, clock: Clock) -> &mut Self {
self.clock = clock;
self
}
/// Set builder to set up the thread pool instance.
#[deprecated(
since="0.1.9",
note="use the `core_threads`, `blocking_threads`, `name_prefix`, \
`keep_alive`, and `stack_size` functions on `runtime::Builder`, \
instead")]
#[doc(hidden)]
pub fn threadpool_builder(&mut self, val: ThreadPoolBuilder) -> &mut Self {
self.threadpool_builder = val;
self
}
/// Set the maximum number of worker threads for the `Runtime`'s thread pool.
///
/// 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;
/// # extern crate futures;
/// # use tokio::runtime;
///
/// # pub fn main() {
/// let mut rt = runtime::Builder::new()
/// .core_threads(4)
/// .build()
/// .unwrap();
/// # }
/// ```
pub fn core_threads(&mut self, val: usize) -> &mut Self {
self.core_threads = val;
self.threadpool_builder.pool_size(val);
self
}
/// Set the maximum number of concurrent blocking sections in the `Runtime`'s
/// thread pool.
///
/// 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;
/// # extern crate futures;
/// # use tokio::runtime;
///
/// # pub fn main() {
/// let mut rt = runtime::Builder::new()
/// .blocking_threads(200)
/// .build();
/// # }
/// ```
pub fn blocking_threads(&mut self, val: usize) -> &mut Self {
self.threadpool_builder.max_blocking(val);
self
}
/// Set the worker thread keep alive duration for threads in the `Runtime`'s
/// thread pool.
///
/// If set, a worker thread will wait for up to the specified duration for
/// work, at which point the thread will shutdown. When work becomes
/// available, a new thread will eventually be spawned to replace the one
/// that shut down.
///
/// When the value is `None`, the thread will wait for work forever.
///
/// The default value is `None`.
///
/// # Examples
///
/// ```
/// # extern crate tokio;
/// # extern crate futures;
/// # use tokio::runtime;
/// use std::time::Duration;
///
/// # pub fn main() {
/// let mut rt = runtime::Builder::new()
/// .keep_alive(Some(Duration::from_secs(30)))
/// .build();
/// # }
/// ```
pub fn keep_alive(&mut self, val: Option<Duration>) -> &mut Self {
self.threadpool_builder.keep_alive(val);
self
}
/// Set name prefix of threads spawned by the `Runtime`'s thread pool.
///
/// 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.
///
/// The default prefix is "tokio-runtime-worker-".
///
/// # Examples
///
/// ```
/// # extern crate tokio;
/// # extern crate futures;
/// # use tokio::runtime;
///
/// # pub fn main() {
/// let mut rt = runtime::Builder::new()
/// .name_prefix("my-pool-")
/// .build();
/// # }
/// ```
pub fn name_prefix<S: Into<String>>(&mut self, val: S) -> &mut Self {
self.threadpool_builder.name_prefix(val);
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;
/// # extern crate futures;
/// # use tokio::runtime;
///
/// # pub fn main() {
/// let mut rt = runtime::Builder::new()
/// .stack_size(32 * 1024)
/// .build();
/// # }
/// ```
pub fn stack_size(&mut self, val: usize) -> &mut Self {
self.threadpool_builder.stack_size(val);
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;
/// # extern crate futures;
/// # use tokio::runtime;
///
/// # pub fn main() {
/// let thread_pool = runtime::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.threadpool_builder.after_start(f);
self
}
/// Execute function `f` before each thread stops.
///
/// This is intended for bookkeeping and monitoring use cases.
///
/// # Examples
///
/// ```
/// # extern crate tokio;
/// # extern crate futures;
/// # use tokio::runtime;
///
/// # pub fn main() {
/// let thread_pool = runtime::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.threadpool_builder.before_stop(f);
self
}
/// Create the configured `Runtime`.
///
/// The returned `ThreadPool` instance is ready to spawn tasks.
///
/// # Examples
///
/// ```
/// # extern crate tokio;
/// # use tokio::runtime::Builder;
/// # pub fn main() {
/// let runtime = Builder::new().build().unwrap();
/// // ... call runtime.run(...)
/// # let _ = runtime;
/// # }
/// ```
pub fn build(&mut self) -> io::Result<Runtime> {
// TODO(stjepang): Once we remove the `threadpool_builder` method, remove this line too.
self.threadpool_builder.pool_size(self.core_threads);
let mut reactor_handles = Vec::new();
let mut timer_handles = Vec::new();
let mut timers = Vec::new();
for _ in 0..self.core_threads {
// Create a new reactor.
let reactor = Reactor::new()?;
reactor_handles.push(reactor.handle());
// Create a new timer.
let timer = Timer::new_with_now(reactor, self.clock.clone());
timer_handles.push(timer.handle());
timers.push(Mutex::new(Some(timer)));
}
// Get a handle to the clock for the runtime.
let clock = self.clock.clone();
let pool = self.threadpool_builder
.around_worker(move |w, enter| {
let index = w.id().to_usize();
tokio_reactor::with_default(&reactor_handles[index], enter, |enter| {
clock::with_default(&clock, enter, |enter| {
timer::with_default(&timer_handles[index], enter, |_| {
w.run();
});
})
});
})
.custom_park(move |worker_id| {
let index = worker_id.to_usize();
timers[index]
.lock()
.unwrap()
.take()
.unwrap()
})
.build();
// To support deprecated `reactor()` function
let reactor = Reactor::new()?;
let reactor_handle = reactor.handle();
Ok(Runtime {
inner: Some(Inner {
reactor_handle,
reactor: Mutex::new(Some(reactor)),
pool,
}),
})
}
}