diagnostics/task_metrics/
component_stats.rs

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1// Copyright 2021 The Fuchsia Authors. All rights reserved.
2// Use of this source code is governed by a BSD-style license that can be
3// found in the LICENSE file.
4
5use crate::task_metrics::measurement::Measurement;
6use crate::task_metrics::runtime_stats_source::RuntimeStatsSource;
7use crate::task_metrics::task_info::TaskInfo;
8use fuchsia_inspect as inspect;
9use futures::lock::Mutex;
10use std::fmt::Debug;
11use std::sync::Arc;
12
13/// Tracks the tasks associated to some component and provides utilities for measuring them.
14pub struct ComponentStats<T: RuntimeStatsSource + Debug> {
15    tasks: Vec<Arc<Mutex<TaskInfo<T>>>>,
16}
17
18impl<T: 'static + RuntimeStatsSource + Debug + Send + Sync> ComponentStats<T> {
19    /// Creates a new `ComponentStats` and starts taking measurements.
20    pub fn new() -> Self {
21        Self { tasks: vec![] }
22    }
23
24    /// Associate a task with this component.
25    pub async fn add_task(&mut self, task: Arc<Mutex<TaskInfo<T>>>) {
26        self.tasks.push(task);
27    }
28
29    /// A `ComponentStats` is alive when:
30    /// - It has not started measuring yet: this means we are still waiting for the diagnostics
31    ///   data to arrive from the runner, or
32    /// - Any of its tasks are alive.
33    pub async fn is_alive(&self) -> bool {
34        let mut any_task_alive = false;
35        for task in &self.tasks {
36            if task.lock().await.is_alive().await {
37                any_task_alive = true;
38            }
39        }
40        any_task_alive
41    }
42
43    /// Takes a runtime info measurement and records it. Drops old ones if the maximum amount is
44    /// exceeded.
45    ///
46    /// Applies to tasks which have TaskState::Alive or TaskState::Terminated.
47    pub async fn measure(&mut self) -> Measurement {
48        let mut result = Measurement::default();
49        for task in self.tasks.iter_mut() {
50            if let Some(measurement) = task.lock().await.measure_if_no_parent().await {
51                result += measurement;
52            }
53        }
54
55        result
56    }
57
58    /// This produces measurements for tasks which have TaskState::TerminatedAndMeasured
59    /// but also have measurement data for the past hour.
60    pub async fn measure_tracked_dead_tasks(&self) -> Measurement {
61        let mut result = Measurement::default();
62
63        for task in self.tasks.iter() {
64            let locked_task = task.lock().await;
65
66            // this implies that `clean_stale()` will take the measurement
67            if locked_task.measurements.no_true_measurements() {
68                continue;
69            }
70
71            if let Some(m) = locked_task.exited_cpu().await {
72                result += m;
73            }
74        }
75
76        result
77    }
78
79    /// Removes all tasks that are not alive.
80    ///
81    /// Returns the koids of the ones that were deleted and the sum of the final measurements
82    /// of the dead tasks. The measurement produced is of Tasks with
83    /// TaskState::TerminatedAndMeasured.
84    pub async fn clean_stale(&mut self) -> (Vec<zx::sys::zx_koid_t>, Measurement) {
85        let mut deleted_koids = vec![];
86        let mut final_tasks = vec![];
87        let mut exited_cpu_time = Measurement::default();
88        while let Some(task) = self.tasks.pop() {
89            let (is_alive, koid) = {
90                let task_guard = task.lock().await;
91                (task_guard.is_alive().await, task_guard.koid())
92            };
93
94            if is_alive {
95                final_tasks.push(task);
96            } else {
97                deleted_koids.push(koid);
98                let locked_task = task.lock().await;
99                if let Some(m) = locked_task.exited_cpu().await {
100                    exited_cpu_time += m;
101                }
102            }
103        }
104        self.tasks = final_tasks;
105        (deleted_koids, exited_cpu_time)
106    }
107
108    pub async fn remove_by_koids(&mut self, remove: &[zx::sys::zx_koid_t]) {
109        let mut final_tasks = vec![];
110        while let Some(task) = self.tasks.pop() {
111            let task_koid = task.lock().await.koid();
112            if !remove.contains(&task_koid) {
113                final_tasks.push(task)
114            }
115        }
116
117        self.tasks = final_tasks;
118    }
119
120    pub async fn gather_dead_tasks(&self) -> Vec<(zx::BootInstant, Arc<Mutex<TaskInfo<T>>>)> {
121        let mut dead_tasks = vec![];
122        for task in &self.tasks {
123            if let Some(t) = task.lock().await.most_recent_measurement().await {
124                dead_tasks.push((t, task.clone()));
125            }
126        }
127
128        dead_tasks
129    }
130
131    /// Writes the stats to inspect under the given node. Returns the number of tasks that were
132    /// written.
133    pub async fn record_to_node(&self, node: &inspect::Node) -> u64 {
134        for task in &self.tasks {
135            task.lock().await.record_to_node(&node);
136        }
137        self.tasks.len() as u64
138    }
139
140    #[cfg(test)]
141    pub async fn total_measurements(&self) -> usize {
142        let mut sum = 0;
143        for task in &self.tasks {
144            sum += task.lock().await.total_measurements();
145        }
146        sum
147    }
148
149    #[cfg(test)]
150    pub fn tasks_mut(&mut self) -> &mut [Arc<Mutex<TaskInfo<T>>>] {
151        &mut self.tasks
152    }
153}
diagnostics/task_metrics/component_stats.rs

diagnostics/task_metrics/
component_stats.rs
