-
Notifications
You must be signed in to change notification settings - Fork 85
Commit
This commit does not belong to any branch on this repository, and may belong to a fork outside of the repository.
Signed-off-by: Palash Nigam <[email protected]>
- Loading branch information
Showing
4 changed files
with
234 additions
and
0 deletions.
There are no files selected for viewing
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
| Original file line number | Diff line number | Diff line change |
|---|---|---|
| @@ -0,0 +1,151 @@ | ||
| //! Module implementing an Open Metrics histogram. | ||
| //! | ||
| //! See [`Summary`] for details. | ||
| use super::{MetricType, TypedMetric}; | ||
| //use owning_ref::OwningRef; | ||
| //use std::iter::{self, once}; | ||
| use std::sync::{Arc, Mutex}; | ||
| use std::time::{Duration, Instant}; | ||
|
|
||
| use quantiles::ckms::CKMS; | ||
|
|
||
| /// Open Metrics [`Summary`] to measure distributions of discrete events. | ||
| #[derive(Debug)] | ||
| pub struct Summary { | ||
| target_quantile: Vec<f64>, | ||
| target_error: f64, | ||
| max_age_buckets: u64, | ||
| max_age_seconds: u64, | ||
| stream_duration: Duration, | ||
| inner: Arc<Mutex<InnerSummary>>, | ||
| } | ||
|
|
||
| impl Clone for Summary { | ||
| fn clone(&self) -> Self { | ||
| Summary { | ||
| target_quantile: self.target_quantile.clone(), | ||
| target_error: self.target_error, | ||
| max_age_buckets: self.max_age_buckets, | ||
| max_age_seconds: self.max_age_seconds, | ||
| stream_duration: self.stream_duration, | ||
| inner: self.inner.clone(), | ||
| } | ||
| } | ||
| } | ||
|
|
||
| #[derive(Debug)] | ||
| pub(crate) struct InnerSummary { | ||
| sum: f64, | ||
| count: u64, | ||
| quantile_streams: Vec<CKMS<f64>>, | ||
| // head_stream is like a cursor which carries the index | ||
| // of the stream in the quantile_streams that we want to query. | ||
| head_stream_idx: u64, | ||
| // timestamp at which the head_stream_idx was last rotated. | ||
| last_rotated_timestamp: Instant, | ||
| } | ||
|
|
||
| impl Summary { | ||
| /// Create a new [`Summary`]. | ||
| pub fn new(max_age_buckets: u64, max_age_seconds: u64, target_quantile: Vec<f64>, target_error: f64) -> Self { | ||
| let mut streams: Vec<CKMS<f64>> = Vec::new(); | ||
| for _ in 0..max_age_buckets { | ||
| streams.push(CKMS::new(target_error)); | ||
| } | ||
|
|
||
| let stream_duration = Duration::from_secs(max_age_seconds / max_age_buckets); | ||
| let last_rotated_timestamp = Instant::now(); | ||
|
|
||
| if target_quantile.iter().any(|&x| x > 1.0 || x < 0.0) { | ||
| panic!("Quantile value out of range"); | ||
| } | ||
|
|
||
| Summary{ | ||
| max_age_buckets, | ||
| max_age_seconds, | ||
| stream_duration, | ||
| target_quantile, | ||
| target_error, | ||
| inner: Arc::new(Mutex::new(InnerSummary { | ||
| sum: Default::default(), | ||
| count: Default::default(), | ||
| quantile_streams: streams, | ||
| head_stream_idx: 0, | ||
| last_rotated_timestamp, | ||
| })) | ||
| } | ||
| } | ||
|
|
||
| /// Observe the given value. | ||
| pub fn observe(&self, v: f64) { | ||
| self.rotate_buckets(); | ||
|
|
||
| let mut inner = self.inner.lock().unwrap(); | ||
| inner.sum += v; | ||
| inner.count += 1; | ||
|
|
||
| // insert quantiles into all streams/buckets. | ||
| for stream in inner.quantile_streams.iter_mut() { | ||
| stream.insert(v); | ||
| } | ||
| } | ||
|
|
||
| /// Retrieve the values of the summary metric. | ||
| pub fn get(&self) -> (f64, u64, Vec<(f64, f64)>) { | ||
| self.rotate_buckets(); | ||
|
|
||
| let inner = self.inner.lock().unwrap(); | ||
| let sum = inner.sum; | ||
| let count = inner.count; | ||
| let mut quantile_values: Vec<(f64, f64)> = Vec::new(); | ||
|
|
||
| for q in self.target_quantile.iter() { | ||
| match inner.quantile_streams[inner.head_stream_idx as usize].query(*q) { | ||
| Some((_, v)) => quantile_values.push((*q, v)), | ||
| None => continue, | ||
| }; | ||
| } | ||
| (sum, count, quantile_values) | ||
| } | ||
|
|
||
| fn rotate_buckets(&self) { | ||
| let mut inner = self.inner.lock().unwrap(); | ||
| if inner.last_rotated_timestamp.elapsed() >= self.stream_duration { | ||
| inner.last_rotated_timestamp = Instant::now(); | ||
| if inner.head_stream_idx == self.max_age_buckets { | ||
| inner.head_stream_idx = 0; | ||
| } else { | ||
| inner.head_stream_idx += 1; | ||
| } | ||
| }; | ||
| } | ||
| } | ||
|
|
||
| impl TypedMetric for Summary { | ||
| const TYPE: MetricType = MetricType::Summary; | ||
| } | ||
|
|
||
| #[cfg(test)] | ||
| mod tests { | ||
| use super::*; | ||
|
|
||
| #[test] | ||
| fn summary() { | ||
| let summary = Summary::new(5, 10, vec![0.5, 0.9, 0.99], 0.01); | ||
| summary.observe(1.0); | ||
| summary.observe(5.0); | ||
| summary.observe(10.0); | ||
|
|
||
| let (s, c, q) = summary.get(); | ||
| assert_eq!(16.0, s); | ||
| assert_eq!(3, c); | ||
| assert_eq!(vec![(0.5, 5.0), (0.9, 10.0), (0.99, 10.0)], q); | ||
| } | ||
|
|
||
| #[test] | ||
| #[should_panic(expected="Quantile value out of range")] | ||
| fn summary_panic() { | ||
| Summary::new(5, 10, vec![1.0, 5.0, 9.0], 0.01); | ||
| } | ||
| } |