diff --git a/tokio/src/macros/cfg.rs b/tokio/src/macros/cfg.rs index 10da95708..7c1dcc612 100644 --- a/tokio/src/macros/cfg.rs +++ b/tokio/src/macros/cfg.rs @@ -1,5 +1,26 @@ #![allow(unused_macros)] +/// Allows specifying arbitrary combinations of features and config flags, +/// which are also propagated to `docsrs` config. +/// +/// Each contained item will have the annotations applied +/// +/// ## Example usage: +/// ```no-compile +/// feature! { +/// #![any( +/// feature = "process", +/// feature = "sync", +/// feature = "rt", +/// tokio_unstable +/// )] +/// /// docs +/// pub struct MyStruct {}; +/// /// docs +/// pub struct AnotherStruct {}; +/// } +/// ``` +/// macro_rules! feature { ( #![$meta:meta] diff --git a/tokio/src/runtime/metrics/runtime.rs b/tokio/src/runtime/metrics/runtime.rs index 188425e7e..047383446 100644 --- a/tokio/src/runtime/metrics/runtime.rs +++ b/tokio/src/runtime/metrics/runtime.rs @@ -342,347 +342,354 @@ impl RuntimeMetrics { .worker_metrics(worker) .thread_id() } + } - cfg_64bit_metrics! { - /// Returns the number of tasks spawned in this runtime since it was created. - /// - /// This count starts at zero when the runtime is created and increases by one each time a task is spawned. - /// - /// The counter is monotonically increasing. It is never decremented or - /// reset to zero. - /// - /// # Examples - /// - /// ``` - /// use tokio::runtime::Handle; - /// - /// #[tokio::main] - /// async fn main() { - /// let metrics = Handle::current().metrics(); - /// - /// let n = metrics.spawned_tasks_count(); - /// println!("Runtime has had {} tasks spawned", n); - /// } - /// ``` - pub fn spawned_tasks_count(&self) -> u64 { - self.handle.inner.spawned_tasks_count() - } - - /// Returns the number of tasks scheduled from **outside** of the runtime. - /// - /// The remote schedule count starts at zero when the runtime is created and - /// increases by one each time a task is woken from **outside** of the - /// runtime. This usually means that a task is spawned or notified from a - /// non-runtime thread and must be queued using the Runtime's injection - /// queue, which tends to be slower. - /// - /// The counter is monotonically increasing. It is never decremented or - /// reset to zero. - /// - /// # Examples - /// - /// ``` - /// use tokio::runtime::Handle; - /// - /// #[tokio::main] - /// async fn main() { - /// let metrics = Handle::current().metrics(); - /// - /// let n = metrics.remote_schedule_count(); - /// println!("{} tasks were scheduled from outside the runtime", n); - /// } - /// ``` - pub fn remote_schedule_count(&self) -> u64 { - self.handle - .inner - .scheduler_metrics() - .remote_schedule_count - .load(Relaxed) - } - - /// Returns the number of times that tasks have been forced to yield back to the scheduler - /// after exhausting their task budgets. - /// - /// This count starts at zero when the runtime is created and increases by one each time a task yields due to exhausting its budget. - /// - /// The counter is monotonically increasing. It is never decremented or - /// reset to zero. - pub fn budget_forced_yield_count(&self) -> u64 { - self.handle - .inner - .scheduler_metrics() - .budget_forced_yield_count - .load(Relaxed) - } - - /// Returns the number of times the given worker thread unparked but - /// performed no work before parking again. - /// - /// The worker no-op count starts at zero when the runtime is created and - /// increases by one each time the worker unparks the thread but finds no - /// new work and goes back to sleep. This indicates a false-positive wake up. - /// - /// The counter is monotonically increasing. It is never decremented or - /// reset to zero. - /// - /// # Arguments - /// - /// `worker` is the index of the worker being queried. The given value must - /// be between 0 and `num_workers()`. The index uniquely identifies a single - /// worker and will continue to identify the worker throughout the lifetime - /// of the runtime instance. - /// - /// # Panics - /// - /// The method panics when `worker` represents an invalid worker, i.e. is - /// greater than or equal to `num_workers()`. - /// - /// # Examples - /// - /// ``` - /// use tokio::runtime::Handle; - /// - /// #[tokio::main] - /// async fn main() { - /// let metrics = Handle::current().metrics(); - /// - /// let n = metrics.worker_noop_count(0); - /// println!("worker 0 had {} no-op unparks", n); - /// } - /// ``` - pub fn worker_noop_count(&self, worker: usize) -> u64 { - self.handle - .inner - .worker_metrics(worker) - .noop_count - .load(Relaxed) - } - - /// Returns the number of tasks the given worker thread stole from - /// another worker thread. - /// - /// This metric only applies to the **multi-threaded** runtime and will - /// always return `0` when using the current thread runtime. - /// - /// The worker steal count starts at zero when the runtime is created and - /// increases by `N` each time the worker has processed its scheduled queue - /// and successfully steals `N` more pending tasks from another worker. - /// - /// The counter is monotonically increasing. It is never decremented or - /// reset to zero. - /// - /// # Arguments - /// - /// `worker` is the index of the worker being queried. The given value must - /// be between 0 and `num_workers()`. The index uniquely identifies a single - /// worker and will continue to identify the worker throughout the lifetime - /// of the runtime instance. - /// - /// # Panics - /// - /// The method panics when `worker` represents an invalid worker, i.e. is - /// greater than or equal to `num_workers()`. - /// - /// # Examples - /// - /// ``` - /// use tokio::runtime::Handle; - /// - /// #[tokio::main] - /// async fn main() { - /// let metrics = Handle::current().metrics(); - /// - /// let n = metrics.worker_steal_count(0); - /// println!("worker 0 has stolen {} tasks", n); - /// } - /// ``` - pub fn worker_steal_count(&self, worker: usize) -> u64 { - self.handle - .inner - .worker_metrics(worker) - .steal_count - .load(Relaxed) - } - - /// Returns the number of times the given worker thread stole tasks from - /// another worker thread. - /// - /// This metric only applies to the **multi-threaded** runtime and will - /// always return `0` when using the current thread runtime. - /// - /// The worker steal count starts at zero when the runtime is created and - /// increases by one each time the worker has processed its scheduled queue - /// and successfully steals more pending tasks from another worker. - /// - /// The counter is monotonically increasing. It is never decremented or - /// reset to zero. - /// - /// # Arguments - /// - /// `worker` is the index of the worker being queried. The given value must - /// be between 0 and `num_workers()`. The index uniquely identifies a single - /// worker and will continue to identify the worker throughout the lifetime - /// of the runtime instance. - /// - /// # Panics - /// - /// The method panics when `worker` represents an invalid worker, i.e. is - /// greater than or equal to `num_workers()`. - /// - /// # Examples - /// - /// ``` - /// use tokio::runtime::Handle; - /// - /// #[tokio::main] - /// async fn main() { - /// let metrics = Handle::current().metrics(); - /// - /// let n = metrics.worker_steal_operations(0); - /// println!("worker 0 has stolen tasks {} times", n); - /// } - /// ``` - pub fn worker_steal_operations(&self, worker: usize) -> u64 { - self.handle - .inner - .worker_metrics(worker) - .steal_operations - .load(Relaxed) - } - - /// Returns the number of tasks the given worker thread has polled. - /// - /// The worker poll count starts at zero when the runtime is created and - /// increases by one each time the worker polls a scheduled task. - /// - /// The counter is monotonically increasing. It is never decremented or - /// reset to zero. - /// - /// # Arguments - /// - /// `worker` is the index of the worker being queried. The given value must - /// be between 0 and `num_workers()`. The index uniquely identifies a single - /// worker and will continue to identify the worker throughout the lifetime - /// of the runtime instance. - /// - /// # Panics - /// - /// The method panics when `worker` represents an invalid worker, i.e. is - /// greater than or equal to `num_workers()`. - /// - /// # Examples - /// - /// ``` - /// use tokio::runtime::Handle; - /// - /// #[tokio::main] - /// async fn main() { - /// let metrics = Handle::current().metrics(); - /// - /// let n = metrics.worker_poll_count(0); - /// println!("worker 0 has polled {} tasks", n); - /// } - /// ``` - pub fn worker_poll_count(&self, worker: usize) -> u64 { - self.handle - .inner - .worker_metrics(worker) - .poll_count - .load(Relaxed) - } - - /// Returns the number of tasks scheduled from **within** the runtime on the - /// given worker's local queue. - /// - /// The local schedule count starts at zero when the runtime is created and - /// increases by one each time a task is woken from **inside** of the - /// runtime on the given worker. This usually means that a task is spawned - /// or notified from within a runtime thread and will be queued on the - /// worker-local queue. - /// - /// The counter is monotonically increasing. It is never decremented or - /// reset to zero. - /// - /// # Arguments - /// - /// `worker` is the index of the worker being queried. The given value must - /// be between 0 and `num_workers()`. The index uniquely identifies a single - /// worker and will continue to identify the worker throughout the lifetime - /// of the runtime instance. - /// - /// # Panics - /// - /// The method panics when `worker` represents an invalid worker, i.e. is - /// greater than or equal to `num_workers()`. - /// - /// # Examples - /// - /// ``` - /// use tokio::runtime::Handle; - /// - /// #[tokio::main] - /// async fn main() { - /// let metrics = Handle::current().metrics(); - /// - /// let n = metrics.worker_local_schedule_count(0); - /// println!("{} tasks were scheduled on the worker's local queue", n); - /// } - /// ``` - pub fn worker_local_schedule_count(&self, worker: usize) -> u64 { - self.handle - .inner - .worker_metrics(worker) - .local_schedule_count - .load(Relaxed) - } - - /// Returns the number of times the given worker thread saturated its local - /// queue. - /// - /// This metric only applies to the **multi-threaded** scheduler. - /// - /// The worker overflow count starts at zero when the runtime is created and - /// increases by one each time the worker attempts to schedule a task - /// locally, but its local queue is full. When this happens, half of the - /// local queue is moved to the injection queue. - /// - /// The counter is monotonically increasing. It is never decremented or - /// reset to zero. - /// - /// # Arguments - /// - /// `worker` is the index of the worker being queried. The given value must - /// be between 0 and `num_workers()`. The index uniquely identifies a single - /// worker and will continue to identify the worker throughout the lifetime - /// of the runtime instance. - /// - /// # Panics - /// - /// The method panics when `worker` represents an invalid worker, i.e. is - /// greater than or equal to `num_workers()`. - /// - /// # Examples - /// - /// ``` - /// use tokio::runtime::Handle; - /// - /// #[tokio::main] - /// async fn main() { - /// let metrics = Handle::current().metrics(); - /// - /// let n = metrics.worker_overflow_count(0); - /// println!("worker 0 has overflowed its queue {} times", n); - /// } - /// ``` - pub fn worker_overflow_count(&self, worker: usize) -> u64 { - self.handle - .inner - .worker_metrics(worker) - .overflow_count - .load(Relaxed) - } + feature! { + #![all( + tokio_unstable, + target_has_atomic = "64" + )] + /// Returns the number of tasks spawned in this runtime since it was created. + /// + /// This count starts at zero when the runtime is created and increases by one each time a task is spawned. + /// + /// The counter is monotonically increasing. It is never decremented or + /// reset to zero. + /// + /// # Examples + /// + /// ``` + /// use tokio::runtime::Handle; + /// + /// #[tokio::main] + /// async fn main() { + /// let metrics = Handle::current().metrics(); + /// + /// let n = metrics.spawned_tasks_count(); + /// println!("Runtime has had {} tasks spawned", n); + /// } + /// ``` + pub fn spawned_tasks_count(&self) -> u64 { + self.handle.inner.spawned_tasks_count() } + /// Returns the number of tasks scheduled from **outside** of the runtime. + /// + /// The remote schedule count starts at zero when the runtime is created and + /// increases by one each time a task is woken from **outside** of the + /// runtime. This usually means that a task is spawned or notified from a + /// non-runtime thread and must be queued using the Runtime's injection + /// queue, which tends to be slower. + /// + /// The counter is monotonically increasing. It is never decremented or + /// reset to zero. + /// + /// # Examples + /// + /// ``` + /// use tokio::runtime::Handle; + /// + /// #[tokio::main] + /// async fn main() { + /// let metrics = Handle::current().metrics(); + /// + /// let n = metrics.remote_schedule_count(); + /// println!("{} tasks were scheduled from outside the runtime", n); + /// } + /// ``` + pub fn remote_schedule_count(&self) -> u64 { + self.handle + .inner + .scheduler_metrics() + .remote_schedule_count + .load(Relaxed) + } + + /// Returns the number of times that tasks have been forced to yield back to the scheduler + /// after exhausting their task budgets. + /// + /// This count starts at zero when the runtime is created and increases by one each time a task yields due to exhausting its budget. + /// + /// The counter is monotonically increasing. It is never decremented or + /// reset to zero. + pub fn budget_forced_yield_count(&self) -> u64 { + self.handle + .inner + .scheduler_metrics() + .budget_forced_yield_count + .load(Relaxed) + } + + /// Returns the number of times the given worker thread unparked but + /// performed no work before parking again. + /// + /// The worker no-op count starts at zero when the runtime is created and + /// increases by one each time the worker unparks the thread but finds no + /// new work and goes back to sleep. This indicates a false-positive wake up. + /// + /// The counter is monotonically increasing. It is never decremented or + /// reset to zero. + /// + /// # Arguments + /// + /// `worker` is the index of the worker being queried. The given value must + /// be between 0 and `num_workers()`. The index uniquely identifies a single + /// worker and will continue to identify the worker throughout the lifetime + /// of the runtime instance. + /// + /// # Panics + /// + /// The method panics when `worker` represents an invalid worker, i.e. is + /// greater than or equal to `num_workers()`. + /// + /// # Examples + /// + /// ``` + /// use tokio::runtime::Handle; + /// + /// #[tokio::main] + /// async fn main() { + /// let metrics = Handle::current().metrics(); + /// + /// let n = metrics.worker_noop_count(0); + /// println!("worker 0 had {} no-op unparks", n); + /// } + /// ``` + pub fn worker_noop_count(&self, worker: usize) -> u64 { + self.handle + .inner + .worker_metrics(worker) + .noop_count + .load(Relaxed) + } + + /// Returns the number of tasks the given worker thread stole from + /// another worker thread. + /// + /// This metric only applies to the **multi-threaded** runtime and will + /// always return `0` when using the current thread runtime. + /// + /// The worker steal count starts at zero when the runtime is created and + /// increases by `N` each time the worker has processed its scheduled queue + /// and successfully steals `N` more pending tasks from another worker. + /// + /// The counter is monotonically increasing. It is never decremented or + /// reset to zero. + /// + /// # Arguments + /// + /// `worker` is the index of the worker being queried. The given value must + /// be between 0 and `num_workers()`. The index uniquely identifies a single + /// worker and will continue to identify the worker throughout the lifetime + /// of the runtime instance. + /// + /// # Panics + /// + /// The method panics when `worker` represents an invalid worker, i.e. is + /// greater than or equal to `num_workers()`. + /// + /// # Examples + /// + /// ``` + /// use tokio::runtime::Handle; + /// + /// #[tokio::main] + /// async fn main() { + /// let metrics = Handle::current().metrics(); + /// + /// let n = metrics.worker_steal_count(0); + /// println!("worker 0 has stolen {} tasks", n); + /// } + /// ``` + pub fn worker_steal_count(&self, worker: usize) -> u64 { + self.handle + .inner + .worker_metrics(worker) + .steal_count + .load(Relaxed) + } + + /// Returns the number of times the given worker thread stole tasks from + /// another worker thread. + /// + /// This metric only applies to the **multi-threaded** runtime and will + /// always return `0` when using the current thread runtime. + /// + /// The worker steal count starts at zero when the runtime is created and + /// increases by one each time the worker has processed its scheduled queue + /// and successfully steals more pending tasks from another worker. + /// + /// The counter is monotonically increasing. It is never decremented or + /// reset to zero. + /// + /// # Arguments + /// + /// `worker` is the index of the worker being queried. The given value must + /// be between 0 and `num_workers()`. The index uniquely identifies a single + /// worker and will continue to identify the worker throughout the lifetime + /// of the runtime instance. + /// + /// # Panics + /// + /// The method panics when `worker` represents an invalid worker, i.e. is + /// greater than or equal to `num_workers()`. + /// + /// # Examples + /// + /// ``` + /// use tokio::runtime::Handle; + /// + /// #[tokio::main] + /// async fn main() { + /// let metrics = Handle::current().metrics(); + /// + /// let n = metrics.worker_steal_operations(0); + /// println!("worker 0 has stolen tasks {} times", n); + /// } + /// ``` + pub fn worker_steal_operations(&self, worker: usize) -> u64 { + self.handle + .inner + .worker_metrics(worker) + .steal_operations + .load(Relaxed) + } + + /// Returns the number of tasks the given worker thread has polled. + /// + /// The worker poll count starts at zero when the runtime is created and + /// increases by one each time the worker polls a scheduled task. + /// + /// The counter is monotonically increasing. It is never decremented or + /// reset to zero. + /// + /// # Arguments + /// + /// `worker` is the index of the worker being queried. The given value must + /// be between 0 and `num_workers()`. The index uniquely identifies a single + /// worker and will continue to identify the worker throughout the lifetime + /// of the runtime instance. + /// + /// # Panics + /// + /// The method panics when `worker` represents an invalid worker, i.e. is + /// greater than or equal to `num_workers()`. + /// + /// # Examples + /// + /// ``` + /// use tokio::runtime::Handle; + /// + /// #[tokio::main] + /// async fn main() { + /// let metrics = Handle::current().metrics(); + /// + /// let n = metrics.worker_poll_count(0); + /// println!("worker 0 has polled {} tasks", n); + /// } + /// ``` + pub fn worker_poll_count(&self, worker: usize) -> u64 { + self.handle + .inner + .worker_metrics(worker) + .poll_count + .load(Relaxed) + } + + /// Returns the number of tasks scheduled from **within** the runtime on the + /// given worker's local queue. + /// + /// The local schedule count starts at zero when the runtime is created and + /// increases by one each time a task is woken from **inside** of the + /// runtime on the given worker. This usually means that a task is spawned + /// or notified from within a runtime thread and will be queued on the + /// worker-local queue. + /// + /// The counter is monotonically increasing. It is never decremented or + /// reset to zero. + /// + /// # Arguments + /// + /// `worker` is the index of the worker being queried. The given value must + /// be between 0 and `num_workers()`. The index uniquely identifies a single + /// worker and will continue to identify the worker throughout the lifetime + /// of the runtime instance. + /// + /// # Panics + /// + /// The method panics when `worker` represents an invalid worker, i.e. is + /// greater than or equal to `num_workers()`. + /// + /// # Examples + /// + /// ``` + /// use tokio::runtime::Handle; + /// + /// #[tokio::main] + /// async fn main() { + /// let metrics = Handle::current().metrics(); + /// + /// let n = metrics.worker_local_schedule_count(0); + /// println!("{} tasks were scheduled on the worker's local queue", n); + /// } + /// ``` + pub fn worker_local_schedule_count(&self, worker: usize) -> u64 { + self.handle + .inner + .worker_metrics(worker) + .local_schedule_count + .load(Relaxed) + } + + /// Returns the number of times the given worker thread saturated its local + /// queue. + /// + /// This metric only applies to the **multi-threaded** scheduler. + /// + /// The worker overflow count starts at zero when the runtime is created and + /// increases by one each time the worker attempts to schedule a task + /// locally, but its local queue is full. When this happens, half of the + /// local queue is moved to the injection queue. + /// + /// The counter is monotonically increasing. It is never decremented or + /// reset to zero. + /// + /// # Arguments + /// + /// `worker` is the index of the worker being queried. The given value must + /// be between 0 and `num_workers()`. The index uniquely identifies a single + /// worker and will continue to identify the worker throughout the lifetime + /// of the runtime instance. + /// + /// # Panics + /// + /// The method panics when `worker` represents an invalid worker, i.e. is + /// greater than or equal to `num_workers()`. + /// + /// # Examples + /// + /// ``` + /// use tokio::runtime::Handle; + /// + /// #[tokio::main] + /// async fn main() { + /// let metrics = Handle::current().metrics(); + /// + /// let n = metrics.worker_overflow_count(0); + /// println!("worker 0 has overflowed its queue {} times", n); + /// } + /// ``` + pub fn worker_overflow_count(&self, worker: usize) -> u64 { + self.handle + .inner + .worker_metrics(worker) + .overflow_count + .load(Relaxed) + } + } + + cfg_unstable_metrics! { + /// Renamed to [`RuntimeMetrics::global_queue_depth`] #[deprecated = "Renamed to global_queue_depth"] #[doc(hidden)] @@ -877,121 +884,127 @@ impl RuntimeMetrics { pub fn poll_count_histogram_bucket_range(&self, bucket: usize) -> Range { self.poll_time_histogram_bucket_range(bucket) } + } - cfg_64bit_metrics! { - /// Returns the number of times the given worker polled tasks with a poll - /// duration within the given bucket's range. - /// - /// Each worker maintains its own histogram and the counts for each bucket - /// starts at zero when the runtime is created. Each time the worker polls a - /// task, it tracks the duration the task poll time took and increments the - /// associated bucket by 1. - /// - /// Each bucket is a monotonically increasing counter. It is never - /// decremented or reset to zero. - /// - /// # Arguments - /// - /// `worker` is the index of the worker being queried. The given value must - /// be between 0 and `num_workers()`. The index uniquely identifies a single - /// worker and will continue to identify the worker throughout the lifetime - /// of the runtime instance. - /// - /// `bucket` is the index of the bucket being queried. The bucket is scoped - /// to the worker. The range represented by the bucket can be queried by - /// calling [`poll_time_histogram_bucket_range()`]. Each worker maintains - /// identical bucket ranges. - /// - /// # Panics - /// - /// The method panics when `worker` represents an invalid worker, i.e. is - /// greater than or equal to `num_workers()` or if `bucket` represents an - /// invalid bucket. - /// - /// # Examples - /// - /// ``` - /// use tokio::runtime::{self, Handle}; - /// - /// fn main() { - /// runtime::Builder::new_current_thread() - /// .enable_metrics_poll_time_histogram() - /// .build() - /// .unwrap() - /// .block_on(async { - /// let metrics = Handle::current().metrics(); - /// let buckets = metrics.poll_time_histogram_num_buckets(); - /// - /// for worker in 0..metrics.num_workers() { - /// for i in 0..buckets { - /// let count = metrics.poll_time_histogram_bucket_count(worker, i); - /// println!("Poll count {}", count); - /// } - /// } - /// }); - /// } - /// ``` - /// - /// [`poll_time_histogram_bucket_range()`]: crate::runtime::RuntimeMetrics::poll_time_histogram_bucket_range - #[track_caller] - pub fn poll_time_histogram_bucket_count(&self, worker: usize, bucket: usize) -> u64 { - self.handle - .inner - .worker_metrics(worker) - .poll_count_histogram - .as_ref() - .map(|histogram| histogram.get(bucket)) - .unwrap_or_default() - } - - #[doc(hidden)] - #[deprecated(note = "use `poll_time_histogram_bucket_count` instead")] - pub fn poll_count_histogram_bucket_count(&self, worker: usize, bucket: usize) -> u64 { - self.poll_time_histogram_bucket_count(worker, bucket) - } - - /// Returns the mean duration of task polls, in nanoseconds. - /// - /// This is an exponentially weighted moving average. Currently, this metric - /// is only provided by the multi-threaded runtime. - /// - /// # Arguments - /// - /// `worker` is the index of the worker being queried. The given value must - /// be between 0 and `num_workers()`. The index uniquely identifies a single - /// worker and will continue to identify the worker throughout the lifetime - /// of the runtime instance. - /// - /// # Panics - /// - /// The method panics when `worker` represents an invalid worker, i.e. is - /// greater than or equal to `num_workers()`. - /// - /// # Examples - /// - /// ``` - /// use tokio::runtime::Handle; - /// - /// #[tokio::main] - /// async fn main() { - /// let metrics = Handle::current().metrics(); - /// - /// let n = metrics.worker_mean_poll_time(0); - /// println!("worker 0 has a mean poll time of {:?}", n); - /// } - /// ``` - #[track_caller] - pub fn worker_mean_poll_time(&self, worker: usize) -> Duration { - let nanos = self - .handle - .inner - .worker_metrics(worker) - .mean_poll_time - .load(Relaxed); - Duration::from_nanos(nanos) - } + feature! { + #![all( + tokio_unstable, + target_has_atomic = "64" + )] + /// Returns the number of times the given worker polled tasks with a poll + /// duration within the given bucket's range. + /// + /// Each worker maintains its own histogram and the counts for each bucket + /// starts at zero when the runtime is created. Each time the worker polls a + /// task, it tracks the duration the task poll time took and increments the + /// associated bucket by 1. + /// + /// Each bucket is a monotonically increasing counter. It is never + /// decremented or reset to zero. + /// + /// # Arguments + /// + /// `worker` is the index of the worker being queried. The given value must + /// be between 0 and `num_workers()`. The index uniquely identifies a single + /// worker and will continue to identify the worker throughout the lifetime + /// of the runtime instance. + /// + /// `bucket` is the index of the bucket being queried. The bucket is scoped + /// to the worker. The range represented by the bucket can be queried by + /// calling [`poll_time_histogram_bucket_range()`]. Each worker maintains + /// identical bucket ranges. + /// + /// # Panics + /// + /// The method panics when `worker` represents an invalid worker, i.e. is + /// greater than or equal to `num_workers()` or if `bucket` represents an + /// invalid bucket. + /// + /// # Examples + /// + /// ``` + /// use tokio::runtime::{self, Handle}; + /// + /// fn main() { + /// runtime::Builder::new_current_thread() + /// .enable_metrics_poll_time_histogram() + /// .build() + /// .unwrap() + /// .block_on(async { + /// let metrics = Handle::current().metrics(); + /// let buckets = metrics.poll_time_histogram_num_buckets(); + /// + /// for worker in 0..metrics.num_workers() { + /// for i in 0..buckets { + /// let count = metrics.poll_time_histogram_bucket_count(worker, i); + /// println!("Poll count {}", count); + /// } + /// } + /// }); + /// } + /// ``` + /// + /// [`poll_time_histogram_bucket_range()`]: crate::runtime::RuntimeMetrics::poll_time_histogram_bucket_range + #[track_caller] + pub fn poll_time_histogram_bucket_count(&self, worker: usize, bucket: usize) -> u64 { + self.handle + .inner + .worker_metrics(worker) + .poll_count_histogram + .as_ref() + .map(|histogram| histogram.get(bucket)) + .unwrap_or_default() } + #[doc(hidden)] + #[deprecated(note = "use `poll_time_histogram_bucket_count` instead")] + pub fn poll_count_histogram_bucket_count(&self, worker: usize, bucket: usize) -> u64 { + self.poll_time_histogram_bucket_count(worker, bucket) + } + + /// Returns the mean duration of task polls, in nanoseconds. + /// + /// This is an exponentially weighted moving average. Currently, this metric + /// is only provided by the multi-threaded runtime. + /// + /// # Arguments + /// + /// `worker` is the index of the worker being queried. The given value must + /// be between 0 and `num_workers()`. The index uniquely identifies a single + /// worker and will continue to identify the worker throughout the lifetime + /// of the runtime instance. + /// + /// # Panics + /// + /// The method panics when `worker` represents an invalid worker, i.e. is + /// greater than or equal to `num_workers()`. + /// + /// # Examples + /// + /// ``` + /// use tokio::runtime::Handle; + /// + /// #[tokio::main] + /// async fn main() { + /// let metrics = Handle::current().metrics(); + /// + /// let n = metrics.worker_mean_poll_time(0); + /// println!("worker 0 has a mean poll time of {:?}", n); + /// } + /// ``` + #[track_caller] + pub fn worker_mean_poll_time(&self, worker: usize) -> Duration { + let nanos = self + .handle + .inner + .worker_metrics(worker) + .mean_poll_time + .load(Relaxed); + Duration::from_nanos(nanos) + } + } + + cfg_unstable_metrics! { /// Returns the number of tasks currently scheduled in the blocking /// thread pool, spawned using `spawn_blocking`. /// @@ -1015,93 +1028,96 @@ impl RuntimeMetrics { pub fn blocking_queue_depth(&self) -> usize { self.handle.inner.blocking_queue_depth() } + } - cfg_net! { - cfg_64bit_metrics! { - /// Returns the number of file descriptors that have been registered with the - /// runtime's I/O driver. - /// - /// # Examples - /// - /// ``` - /// use tokio::runtime::Handle; - /// - /// #[tokio::main] - /// async fn main() { - /// let metrics = Handle::current().metrics(); - /// - /// let registered_fds = metrics.io_driver_fd_registered_count(); - /// println!("{} fds have been registered with the runtime's I/O driver.", registered_fds); - /// - /// let deregistered_fds = metrics.io_driver_fd_deregistered_count(); - /// - /// let current_fd_count = registered_fds - deregistered_fds; - /// println!("{} fds are currently registered by the runtime's I/O driver.", current_fd_count); - /// } - /// ``` - pub fn io_driver_fd_registered_count(&self) -> u64 { - self.with_io_driver_metrics(|m| { - m.fd_registered_count.load(Relaxed) - }) - } - - /// Returns the number of file descriptors that have been deregistered by the - /// runtime's I/O driver. - /// - /// # Examples - /// - /// ``` - /// use tokio::runtime::Handle; - /// - /// #[tokio::main] - /// async fn main() { - /// let metrics = Handle::current().metrics(); - /// - /// let n = metrics.io_driver_fd_deregistered_count(); - /// println!("{} fds have been deregistered by the runtime's I/O driver.", n); - /// } - /// ``` - pub fn io_driver_fd_deregistered_count(&self) -> u64 { - self.with_io_driver_metrics(|m| { - m.fd_deregistered_count.load(Relaxed) - }) - } - - /// Returns the number of ready events processed by the runtime's - /// I/O driver. - /// - /// # Examples - /// - /// ``` - /// use tokio::runtime::Handle; - /// - /// #[tokio::main] - /// async fn main() { - /// let metrics = Handle::current().metrics(); - /// - /// let n = metrics.io_driver_ready_count(); - /// println!("{} ready events processed by the runtime's I/O driver.", n); - /// } - /// ``` - pub fn io_driver_ready_count(&self) -> u64 { - self.with_io_driver_metrics(|m| m.ready_count.load(Relaxed)) - } - - fn with_io_driver_metrics(&self, f: F) -> u64 - where - F: Fn(&super::IoDriverMetrics) -> u64, - { - // TODO: Investigate if this should return 0, most of our metrics always increase - // thus this breaks that guarantee. - self.handle - .inner - .driver() - .io - .as_ref() - .map(|h| f(&h.metrics)) - .unwrap_or(0) - } + feature! { + #![all( + tokio_unstable, + target_has_atomic = "64", + feature = "net" + )] + /// Returns the number of file descriptors that have been registered with the + /// runtime's I/O driver. + /// + /// # Examples + /// + /// ``` + /// use tokio::runtime::Handle; + /// + /// #[tokio::main] + /// async fn main() { + /// let metrics = Handle::current().metrics(); + /// + /// let registered_fds = metrics.io_driver_fd_registered_count(); + /// println!("{} fds have been registered with the runtime's I/O driver.", registered_fds); + /// + /// let deregistered_fds = metrics.io_driver_fd_deregistered_count(); + /// + /// let current_fd_count = registered_fds - deregistered_fds; + /// println!("{} fds are currently registered by the runtime's I/O driver.", current_fd_count); + /// } + /// ``` + pub fn io_driver_fd_registered_count(&self) -> u64 { + self.with_io_driver_metrics(|m| { + m.fd_registered_count.load(Relaxed) + }) + } + + /// Returns the number of file descriptors that have been deregistered by the + /// runtime's I/O driver. + /// + /// # Examples + /// + /// ``` + /// use tokio::runtime::Handle; + /// + /// #[tokio::main] + /// async fn main() { + /// let metrics = Handle::current().metrics(); + /// + /// let n = metrics.io_driver_fd_deregistered_count(); + /// println!("{} fds have been deregistered by the runtime's I/O driver.", n); + /// } + /// ``` + pub fn io_driver_fd_deregistered_count(&self) -> u64 { + self.with_io_driver_metrics(|m| { + m.fd_deregistered_count.load(Relaxed) + }) + } + + /// Returns the number of ready events processed by the runtime's + /// I/O driver. + /// + /// # Examples + /// + /// ``` + /// use tokio::runtime::Handle; + /// + /// #[tokio::main] + /// async fn main() { + /// let metrics = Handle::current().metrics(); + /// + /// let n = metrics.io_driver_ready_count(); + /// println!("{} ready events processed by the runtime's I/O driver.", n); + /// } + /// ``` + pub fn io_driver_ready_count(&self) -> u64 { + self.with_io_driver_metrics(|m| m.ready_count.load(Relaxed)) + } + + fn with_io_driver_metrics(&self, f: F) -> u64 + where + F: Fn(&super::IoDriverMetrics) -> u64, + { + // TODO: Investigate if this should return 0, most of our metrics always increase + // thus this breaks that guarantee. + self.handle + .inner + .driver() + .io + .as_ref() + .map(|h| f(&h.metrics)) + .unwrap_or(0) } - } } }