An initial pass at updating `tokio-threadpool` to `std::future`. The
codebase and tests both now run using `std::future` but the wake
mechanism is not ideal. Follow up work will be required to improve on
this.
Refs: #1200
## Motivation
When the thread pool shuts down, futures that have been polled at least once but not completed yet are simply leaked. We should drop them instead.
## Solution
Multiple changes are introduced:
* Tasks are assigned a home worker the first time they are polled.
* Each worker contains a set of tasks (`Arc<Task>`) it is home to. When a task is assigned a home worker, it is registered in that worker's set of tasks. When the task is completed, it is unregistered from the set.
* When the thread pool shuts down and after all worker threads stop, the remaining tasks in workers' sets are aborted, i.e. they are switched to the `Aborted` state and their `Future`s are dropped.
* The thread pool shutdown process is refactored to make it more robust. We don't track the number of active threads manually anymore. Instead, there's `Arc<ShutdownTrigger>` that aborts remaining tasks and completes the `Shutdown` future once it gets destroyed (when all `Worker`s and `ThreadPool` get dropped because they're the only ones to contain strong references to the `ShutdownTrigger`).
Closes#424Closes#428
This also bumps a number of sub crates:
* tokio-executor (0.1.3)
* tokio-io (0.1.8)
* tokio-reactor (0.1.4)
* tokio-threadpool (0.1.6)
* tokio-timer (0.2.6)
* tokio-udp (0.1.2)
The futures 0.2 crate is not intended for widespread usage. Also, the
futures team is exploring the compat shim route.
If futures 0.3 support is added to Tokio 0.1, then a different
integration route will be explored, making the current code unhelpful.
* Normalize links to docs.rs/CRATE/M.N/...
docs.rs is smart enough to show docs for the latest M.N.P release when
M.N is used in the link. For example:
https://docs.rs/mio/0.6/mio/struct.Poll.html
..will show mio 0.6.14 and later docs. While using the `M.N.*`
(ASTERISK) syntax also works, `M.N` is the more common usage, so
standarize a few existing links to that format.
* Fix missing or malformed rustdoc links
* executor lib rustdoc minor format change
* Promote tokio-threadpool crate level comments to rustdoc
* Replace hidden tokio::executor::thread_pool docs with deprecation note
* Fix typo/simplify util module rustdoc
* Reuse some tokio::executor::thread_pool rustdoc for the crate
Relates to #421
This patch adds a `blocking` to `tokio-threadpool`. This function serves
as a way to annotate sections of code that will perform blocking
operations. This informs the thread pool that an additional thread needs
to be spawned to replace the current thread, which will no longer be
able to process the work queue.
* Allow customizing the threadpool's parker
This patch allows the user of threadpool to customize how the worker
threads park themselves. This allows custom parking logic to be
injected. For example, this allows embedding a timer on each worker
thread.
* Call `park` instance every so often.
Since the `park` is now customizable, it might have logic that must be
called every so often. For example, a timer might have timeouts that it
must expire.
Currently, if a worker is very busy, it won't call into the `park`
instance. This patch changes this so that after every 32 task
invocations, `park` is called with a duration of zero.
* Fix races.
This mostly pulls in changes from rust-lang-nursery/futures-rs#881, but
also updates Registration to be a bit more obvious as to what is going
on.
* Reduce spurious wakeups caused by Reactor
This patch adds an ABA guard on token values before registering them
with Mio. This allows catching token reuse and avoid the notification.
This is needed for OS X as the notification is used to determine that a
TCP connect has completed. A spurious notification can potentially cause
write failures.
Currently, if a thread pool instance is dropped without being shutdown,
the workers will run indefinitely. This is not ideal as it leaks the
threadpool.
This patch forces the thread pool to shutdown on drop.
Closes#151
This patch is an intial implementation of the Tokio runtime. The Tokio
runtime provides an out of the box configuration for running I/O heavy
asynchronous applications.
As of now, the Tokio runtime is a combination of a work-stealing thread
pool as well as a background reactor to drive I/O resources.
This patch also includes tokio-executor, a hopefully short lived crate
that is based on the futures 0.2 executor RFC.
* Implement `Park` for `Reactor`
This enables the reactor to be used as the thread parker for executors.
This also adds an `Error` component to `Park`. With this change, a
`Reactor` and a `CurrentThread` can be combined to achieve the
capabilities of tokio-core.
Gurwinder Singh