From 7058272bfca2878dce81b2e006e2b722bab34949 Mon Sep 17 00:00:00 2001 From: Mindaugas Vinkelis Date: Thu, 21 Nov 2024 12:23:34 +0200 Subject: [PATCH 1/2] Measure metrics latency --- stress/Cargo.toml | 5 + stress/src/metrics_latency.rs | 300 ++++++++++++++++++++++++++++++++++ 2 files changed, 305 insertions(+) create mode 100644 stress/src/metrics_latency.rs diff --git a/stress/Cargo.toml b/stress/Cargo.toml index 6d3dd4dd1f..efe4a56ff4 100644 --- a/stress/Cargo.toml +++ b/stress/Cargo.toml @@ -19,6 +19,11 @@ name = "metrics_histogram" path = "src/metrics_histogram.rs" doc = false +[[bin]] # Bin to run measure latency in various conditions +name = "metrics_latency" +path = "src/metrics_latency.rs" +doc = false + [[bin]] # Bin to run the metrics overflow stress tests name = "metrics_overflow" path = "src/metrics_overflow.rs" diff --git a/stress/src/metrics_latency.rs b/stress/src/metrics_latency.rs new file mode 100644 index 0000000000..8f75a1f425 --- /dev/null +++ b/stress/src/metrics_latency.rs @@ -0,0 +1,300 @@ +use std::{ + collections::{BTreeMap, HashMap}, + sync::{ + atomic::{AtomicBool, AtomicU64, Ordering}, + Arc, Mutex, Weak, + }, + time::{Duration, Instant}, +}; + +use opentelemetry::{metrics::MeterProvider, KeyValue}; +use opentelemetry_sdk::{ + metrics::{ + data::{self, ResourceMetrics}, + reader::MetricReader, + InstrumentKind, ManualReader, MetricError, Pipeline, SdkMeterProvider, Temporality, + }, + Resource, +}; + +// copy/paste from opentelemetry-sdk/benches/metric.rs +#[derive(Clone, Debug)] +pub struct SharedReader(Arc); + +impl SharedReader { + pub fn new(reader: R) -> Self + where + R: MetricReader, + { + Self(Arc::new(reader)) + } +} + +impl MetricReader for SharedReader { + fn register_pipeline(&self, pipeline: Weak) { + self.0.register_pipeline(pipeline) + } + + fn collect(&self, rm: &mut ResourceMetrics) -> Result<(), MetricError> { + self.0.collect(rm) + } + + fn force_flush(&self) -> Result<(), MetricError> { + self.0.force_flush() + } + + fn shutdown(&self) -> Result<(), MetricError> { + self.0.shutdown() + } + + fn temporality(&self, kind: InstrumentKind) -> Temporality { + self.0.temporality(kind) + } +} + +fn main() { + let available_threads: usize = std::thread::available_parallelism().map_or(1, |p| p.get()); + + for threads_count in [available_threads / 3, available_threads * 3] { + println!("*** updates, using {threads_count} threads ***"); + measure_update_latency(&format!("no attribs"), threads_count, |_i, _j| []); + measure_update_latency(&format!("1 attrib"), threads_count, |_i, _j| { + [KeyValue::new("some_key", 1)] + }); + + measure_update_latency(&format!("9 attribs"), threads_count, |_i, _j| { + // for http.server.request.duration as defined in https://opentelemetry.io/docs/specs/semconv/http/http-metrics/ + [ + KeyValue::new("http.request.method", "GET"), + KeyValue::new("url.scheme", "not_found"), + KeyValue::new("error.type", 404), + KeyValue::new("http.response.status_code", 404), + KeyValue::new("http.route", "testing/metrics/latency"), + KeyValue::new("network.protocol.name", "http"), + KeyValue::new("network.protocol.version", 2), + KeyValue::new("server.address", "example.com"), + KeyValue::new("server.port", 8080), + ] + }); + println!("*** inserts, using {threads_count} threads ***"); + measure_update_latency(&format!("1 attrib"), threads_count, |i, j| { + [KeyValue::new(format!("some_key{i}"), j as i64)] + }); + + measure_update_latency(&format!("10 attribs"), threads_count, |i, j| { + [ + KeyValue::new(format!("random{i}"), j as i64), + KeyValue::new("http.request.method", "GET"), + KeyValue::new("url.scheme", "not_found"), + KeyValue::new("error.type", 404), + KeyValue::new("http.response.status_code", 404), + KeyValue::new("http.route", "testing/metrics/latency"), + KeyValue::new("network.protocol.name", "http"), + KeyValue::new("network.protocol.version", 2), + KeyValue::new("server.address", "example.com"), + KeyValue::new("server.port", 8080), + ] + }); + println!("*** mix mostly updates (200 attribute-sets), using {threads_count} threads ***"); + measure_update_latency(&format!("10 attribs"), threads_count, |_i, j| { + [ + KeyValue::new("random", (j % 200) as i64), + KeyValue::new("http.request.method", "GET"), + KeyValue::new("url.scheme", "not_found"), + KeyValue::new("error.type", 404), + KeyValue::new("http.response.status_code", 404), + KeyValue::new("http.route", "testing/metrics/latency"), + KeyValue::new("network.protocol.name", "http"), + KeyValue::new("network.protocol.version", 2), + KeyValue::new("server.address", "example.com"), + KeyValue::new("server.port", 8080), + ] + }); + } +} + +fn measure_update_latency( + msg: &str, + threads_count: usize, + attribs: fn(usize, u64) -> [KeyValue; N], +) { + let reader = SharedReader::new( + ManualReader::builder() + .with_temporality(Temporality::Delta) + .build(), + ); + let provider = SdkMeterProvider::builder() + .with_reader(reader.clone()) + .build(); + let histogram = provider.meter("test").u64_counter("hello").build(); + let mut threads = Vec::new(); + let mut stats = Vec::new(); + stats.resize_with(threads_count, || { + Arc::new(Mutex::new(HashMap::::new())) + }); + let total_iterations = Arc::new(AtomicU64::new(0)); + let iterate_flag = Arc::new(AtomicBool::new(true)); + let start = Instant::now(); + // run multiple threads and measure how time it takes to update metric + for thread_idx in 0..threads_count { + let hist = histogram.clone(); + let stat = stats[thread_idx].clone(); + let iterate_flag = iterate_flag.clone(); + let total_iterations = total_iterations.clone(); + threads.push(std::thread::spawn(move || { + let mut stat = stat.lock().unwrap(); + let mut iter_idx = 0; + while iterate_flag.load(Ordering::Acquire) { + let kv = attribs(thread_idx, iter_idx); + let start = Instant::now(); + hist.add(1, &kv); + let curr = stat.entry(start.elapsed().as_nanos() as u64).or_default(); + *curr += 1; + iter_idx += 1; + } + total_iterations.fetch_add(iter_idx, Ordering::AcqRel); + })); + } + let mut total_count = 0; + while start.elapsed() < Duration::from_secs(1) { + // we should collect frequently enough, so that inserts doesn't reach overflow (2000) + // but not too frequently, so that it will be visible in p99 (have effect on +1% of measurements) + // with 0.3ms sleep, collect will be called around 1900-2500 times (depending on load) + // so we might get around ~2M/s inserts, until they start overflow + // and it's low enough so it shouldn't influence 1% of updates (p99). + std::thread::sleep(Duration::from_micros(300)); + total_count += collect_and_return_count(&reader); + } + iterate_flag.store(false, Ordering::Release); + threads.into_iter().for_each(|t| { + t.join().unwrap(); + }); + total_count += collect_and_return_count(&reader); + + let total_measurements = total_iterations.load(Ordering::Acquire); + assert_eq!(total_count, total_measurements); + + let stats = stats + .into_iter() + .map(|s| Arc::into_inner(s).unwrap().into_inner().unwrap()) + .flat_map(|s| s.into_iter()) + .fold(BTreeMap::::default(), |mut acc, (time, count)| { + *acc.entry(time).or_default() += count; + acc + }); + + let sum = stats.iter().fold(0, |mut acc, (&time, &count)| { + acc += time * count; + acc + }); + + println!("{msg}"); + println!("\titer {}", format_count(total_measurements)); + println!("\tavg {}", format_time(sum / total_measurements as u64)); + println!( + "\tp50 {}", + format_time(get_percentile_value(total_measurements, &stats, 50)) + ); + println!( + "\tp95 {}", + format_time(get_percentile_value(total_measurements, &stats, 95)) + ); + println!( + "\tp99 {}", + format_time(get_percentile_value(total_measurements, &stats, 99)) + ); +} + +fn collect_and_return_count(reader: &SharedReader) -> u64 { + let mut rm = ResourceMetrics { + resource: Resource::empty(), + scope_metrics: Vec::new(), + }; + reader.collect(&mut rm).unwrap(); + rm.scope_metrics + .into_iter() + .flat_map(|sm| sm.metrics.into_iter()) + .flat_map(|m| { + m.data + .as_any() + .downcast_ref::>() + .unwrap() + .data_points + .clone() + .into_iter() + }) + .map(|dp| dp.value) + .sum() +} + +fn get_percentile_value( + total_measurements: u64, + stats: &BTreeMap, + percentile: u64, +) -> u64 { + assert!(percentile > 0 && percentile < 100); + let break_point = ((total_measurements as f64 * percentile as f64) / 100.0) as u64; + let mut iter = stats.iter().peekable(); + let mut sum = 0; + while let Some(left) = iter.next() { + sum += left.1; + if let Some(&right) = iter.peek() { + let next_sum = sum + right.1; + if next_sum > break_point { + // interpolate + let diff = (next_sum - sum) as f32; + let ratio = (break_point - sum) as f32 / diff; + let time_diff = (right.0 - left.0) as f32; + return *left.0 + (time_diff * ratio) as u64; + } + } + } + 0 +} + +fn format_count(count: u64) -> String { + let count = count as f64; + let (val, symbol) = if count > 1000000.0 { + (count / 1000000.0, "M") + } else if count > 1000.0 { + (count / 1000.0, "K") + } else { + (count, "") + }; + if val > 100.0 { + format!("{val:>5.1}{symbol}") + } else if val > 10.0 { + format!("{val:>5.2}{symbol}") + } else { + format!("{val:>5.3}{symbol}") + } +} + +fn format_time(nanos: u64) -> String { + let nanos = nanos as f64; + let (val, symbol) = if nanos > 1000000.0 { + (nanos / 1000000.0, "ms") + } else if nanos > 1000.0 { + (nanos / 1000.0, "μs") + } else { + (nanos, "ns") + }; + if val > 100.0 { + format!("{val:>5.1}{symbol}") + } else if val > 10.0 { + format!("{val:>5.2}{symbol}") + } else { + format!("{val:>5.3}{symbol}") + } +} + +#[test] +fn test_format_time() { + assert_eq!("12.00ns", format_time(12)); + assert_eq!("123.0ns", format_time(123)); + assert_eq!("1.234μs", format_time(1234)); + assert_eq!("12.35μs", format_time(12349)); + assert_eq!("123.4μs", format_time(123400)); + assert_eq!("1.235ms", format_time(1234900)); + assert_eq!("12.34ms", format_time(12340000)); +} From 8898ac5b9907f001c4704552153c09b12e6bd1de Mon Sep 17 00:00:00 2001 From: Mindaugas Vinkelis Date: Mon, 25 Nov 2024 09:07:12 +0200 Subject: [PATCH 2/2] Adaptive collect interval --- stress/src/metrics_latency.rs | 89 +++++++++++++++++++++++++---------- 1 file changed, 64 insertions(+), 25 deletions(-) diff --git a/stress/src/metrics_latency.rs b/stress/src/metrics_latency.rs index 8f75a1f425..82e683b6f6 100644 --- a/stress/src/metrics_latency.rs +++ b/stress/src/metrics_latency.rs @@ -1,10 +1,13 @@ use std::{ + cell::RefCell, collections::{BTreeMap, HashMap}, sync::{ atomic::{AtomicBool, AtomicU64, Ordering}, Arc, Mutex, Weak, }, + thread::{sleep, JoinHandle}, time::{Duration, Instant}, + u64, }; use opentelemetry::{metrics::MeterProvider, KeyValue}; @@ -16,6 +19,12 @@ use opentelemetry_sdk::{ }, Resource, }; +use rand::{rngs, Rng, SeedableRng}; + +thread_local! { + /// Store random number generator for each thread + static CURRENT_RNG: RefCell = RefCell::new(rngs::SmallRng::from_entropy()); +} // copy/paste from opentelemetry-sdk/benches/metric.rs #[derive(Clone, Debug)] @@ -55,14 +64,14 @@ impl MetricReader for SharedReader { fn main() { let available_threads: usize = std::thread::available_parallelism().map_or(1, |p| p.get()); - for threads_count in [available_threads / 3, available_threads * 3] { + for threads_count in [available_threads / 4, available_threads * 4] { println!("*** updates, using {threads_count} threads ***"); - measure_update_latency(&format!("no attribs"), threads_count, |_i, _j| []); - measure_update_latency(&format!("1 attrib"), threads_count, |_i, _j| { + measure_update_latency(&format!("no attribs"), threads_count, 10000000, |_i, _j| []); + measure_update_latency(&format!("1 attrib"), threads_count, 10000000, |_i, _j| { [KeyValue::new("some_key", 1)] }); - measure_update_latency(&format!("9 attribs"), threads_count, |_i, _j| { + measure_update_latency(&format!("9 attribs"), threads_count, 10000000, |_i, _j| { // for http.server.request.duration as defined in https://opentelemetry.io/docs/specs/semconv/http/http-metrics/ [ KeyValue::new("http.request.method", "GET"), @@ -77,11 +86,11 @@ fn main() { ] }); println!("*** inserts, using {threads_count} threads ***"); - measure_update_latency(&format!("1 attrib"), threads_count, |i, j| { + measure_update_latency(&format!("1 attrib"), threads_count, 1500, |i, j| { [KeyValue::new(format!("some_key{i}"), j as i64)] }); - measure_update_latency(&format!("10 attribs"), threads_count, |i, j| { + measure_update_latency(&format!("10 attribs"), threads_count, 1500, |i, j| { [ KeyValue::new(format!("random{i}"), j as i64), KeyValue::new("http.request.method", "GET"), @@ -95,10 +104,15 @@ fn main() { KeyValue::new("server.port", 8080), ] }); - println!("*** mix mostly updates (200 attribute-sets), using {threads_count} threads ***"); - measure_update_latency(&format!("10 attribs"), threads_count, |_i, j| { + println!("*** mix mostly updates (~10% inserts), using {threads_count} threads ***"); + measure_update_latency(&format!("10 attribs"), threads_count, 10000, |_i, j| { + let randomness: i64 = 20 + - CURRENT_RNG.with(|rng| { + let mut rng = rng.borrow_mut(); + rng.gen_range(0..20) + }); [ - KeyValue::new("random", (j % 200) as i64), + KeyValue::new("random", (j / 10) as i64 + randomness), KeyValue::new("http.request.method", "GET"), KeyValue::new("url.scheme", "not_found"), KeyValue::new("error.type", 404), @@ -116,6 +130,7 @@ fn main() { fn measure_update_latency( msg: &str, threads_count: usize, + collect_around: u64, attribs: fn(usize, u64) -> [KeyValue; N], ) { let reader = SharedReader::new( @@ -134,7 +149,6 @@ fn measure_update_latency( }); let total_iterations = Arc::new(AtomicU64::new(0)); let iterate_flag = Arc::new(AtomicBool::new(true)); - let start = Instant::now(); // run multiple threads and measure how time it takes to update metric for thread_idx in 0..threads_count { let hist = histogram.clone(); @@ -155,25 +169,48 @@ fn measure_update_latency( total_iterations.fetch_add(iter_idx, Ordering::AcqRel); })); } + + let total_measurements = collect_measurements(reader, threads, iterate_flag, collect_around); + + assert_eq!(total_measurements, total_iterations.load(Ordering::Acquire)); + + print_stats(msg, stats, total_measurements); +} + +fn collect_measurements( + reader: SharedReader, + threads: Vec>, + iterate_flag: Arc, + collect_around: u64, +) -> u64 { + let start = Instant::now(); let mut total_count = 0; + let mut wait_for_next_collect = Duration::from_micros(500); while start.elapsed() < Duration::from_secs(1) { - // we should collect frequently enough, so that inserts doesn't reach overflow (2000) - // but not too frequently, so that it will be visible in p99 (have effect on +1% of measurements) - // with 0.3ms sleep, collect will be called around 1900-2500 times (depending on load) - // so we might get around ~2M/s inserts, until they start overflow - // and it's low enough so it shouldn't influence 1% of updates (p99). - std::thread::sleep(Duration::from_micros(300)); - total_count += collect_and_return_count(&reader); + sleep(wait_for_next_collect); + let collected = collect_and_return_count(&reader); + // calculate wait interval so that the next collect cycle would be close to `collect_around` + let ratio = collected as f64 / collect_around as f64; + let clamped = if ratio > 2.0 { + 2.0 + } else if ratio < 0.5 { + 0.5 + } else { + ratio + }; + wait_for_next_collect = + Duration::from_micros((wait_for_next_collect.as_micros() as f64 / clamped) as u64); + total_count += collected; } iterate_flag.store(false, Ordering::Release); threads.into_iter().for_each(|t| { t.join().unwrap(); }); total_count += collect_and_return_count(&reader); + total_count +} - let total_measurements = total_iterations.load(Ordering::Acquire); - assert_eq!(total_count, total_measurements); - +fn print_stats(msg: &str, stats: Vec>>>, total_measurements: u64) { let stats = stats .into_iter() .map(|s| Arc::into_inner(s).unwrap().into_inner().unwrap()) @@ -189,20 +226,22 @@ fn measure_update_latency( }); println!("{msg}"); - println!("\titer {}", format_count(total_measurements)); - println!("\tavg {}", format_time(sum / total_measurements as u64)); + println!("\titer {}", format_count(total_measurements)); println!( - "\tp50 {}", + "\tp50 {}", format_time(get_percentile_value(total_measurements, &stats, 50)) ); println!( - "\tp95 {}", + "\tp95 {}", format_time(get_percentile_value(total_measurements, &stats, 95)) ); println!( - "\tp99 {}", + "\tp99 {}", format_time(get_percentile_value(total_measurements, &stats, 99)) ); + println!("\tavg {}", format_time(sum / total_measurements as u64)); + println!("\tbest {}", format_time(*stats.iter().next().unwrap().0)); + println!("\tworst {}", format_time(*stats.iter().last().unwrap().0)); } fn collect_and_return_count(reader: &SharedReader) -> u64 {