[chore] Use elapsed() if possible when calculating durations (#750)

Author: danielsn

bin_tests/src/lib.rs

@@ -157,7 +157,7 @@ macro_rules! timeit {
     ($op_name:literal, $op:block) => {{
         let start = std::time::Instant::now();
         let res = $op;
-        let delta = std::time::Instant::now().duration_since(start);
+        let delta = start.elapsed();
         println!(
             concat!($op_name, " took {} ms"),
             delta.as_secs_f64() * 1000.0

crashtracker/src/collector/crash_handler.rs

@@ -155,7 +155,7 @@ fn reap_child_non_blocking(pid: Pid, timeout_ms: u32) -> anyhow::Result<bool> {
     loop {
         match waitpid(pid, Some(WaitPidFlag::WNOHANG)) {
             Ok(WaitStatus::StillAlive) => {
-                if Instant::now().duration_since(start_time) > timeout {
+                if start_time.elapsed() > timeout {
                     return Err(anyhow::anyhow!("Timeout waiting for child process to exit"));
                 }
             }

crashtracker/src/crash_info/telemetry.rs

@@ -136,8 +136,8 @@ impl TelemetryCrashUploader {
 
         let tracer_time = match &crash_info.timestamp {
             Some(ts) => ts.timestamp() as u64,
-            None => SystemTime::now()
-                .duration_since(SystemTime::UNIX_EPOCH)
+            None => SystemTime::UNIX_EPOCH
+                .elapsed()
                 .map(|d| d.as_secs())
                 .unwrap_or(0),
         };

data-pipeline/examples/send-traces-with-stats.rs

@@ -7,7 +7,7 @@ use data_pipeline::trace_exporter::{
 use datadog_trace_protobuf::pb;
 use std::{
     collections::HashMap,
-    time::{Duration, SystemTime, UNIX_EPOCH},
+    time::{Duration, UNIX_EPOCH},
 };
 
 fn get_span(now: i64, trace_id: u64, span_id: u64) -> pb::Span {
@@ -44,10 +44,7 @@ fn main() {
         .enable_stats(Duration::from_secs(10))
         .build()
         .unwrap();
-    let now = SystemTime::now()
-        .duration_since(UNIX_EPOCH)
-        .unwrap()
-        .as_nanos() as i64;
+    let now = UNIX_EPOCH.elapsed().unwrap().as_nanos() as i64;
 
     let mut traces = Vec::new();
     for trace_id in 1..=100 {

data-pipeline/src/span_concentrator/mod.rs

@@ -14,10 +14,8 @@ mod aggregation;
 /// Return a Duration between t and the unix epoch
 /// If t is before the unix epoch return 0
 fn system_time_to_unix_duration(t: SystemTime) -> Duration {
-    match t.duration_since(time::UNIX_EPOCH) {
-        Err(_) => Duration::from_nanos(0),
-        Ok(d) => d,
-    }
+    t.duration_since(time::UNIX_EPOCH)
+        .unwrap_or(Duration::from_nanos(0))
 }
 
 /// Align a timestamp on the start of a bucket

ddtelemetry/examples/tm-metrics-worker-test.rs

@@ -10,7 +10,7 @@ macro_rules! timeit {
     ($op_name:literal, $op:block) => {{
         let start = std::time::Instant::now();
         let res = $op;
-        let delta = std::time::Instant::now().duration_since(start);
+        let delta = start.elapsed();
         println!(
             concat!($op_name, " took {} ms"),
             delta.as_secs_f64() * 1000.0

ddtelemetry/examples/tm-ping.rs

@@ -32,10 +32,7 @@ fn build_request<'a>(
 ) -> data::Telemetry<'a> {
     data::Telemetry {
         api_version: data::ApiVersion::V1,
-        tracer_time: SystemTime::now()
-            .duration_since(SystemTime::UNIX_EPOCH)
-            .map(|d| d.as_secs())
-            .unwrap_or(0),
+        tracer_time: SystemTime::UNIX_EPOCH.elapsed().map_or(0, |d| d.as_secs()),
         runtime_id: "runtime_id",
         seq_id: seq_id(),
         application,

ddtelemetry/examples/tm-send-sketch.rs

@@ -30,10 +30,7 @@ fn build_request<'a>(
 ) -> data::Telemetry<'a> {
     data::Telemetry {
         api_version: data::ApiVersion::V1,
-        tracer_time: SystemTime::now()
-            .duration_since(SystemTime::UNIX_EPOCH)
-            .map(|d| d.as_secs())
-            .unwrap_or(0),
+        tracer_time: SystemTime::UNIX_EPOCH.elapsed().map_or(0, |d| d.as_secs()),
         runtime_id: "runtime_id",
         seq_id: seq_id(),
         application,

ddtelemetry/examples/tm-worker-test.rs

@@ -13,7 +13,7 @@ macro_rules! timeit {
     ($op_name:literal, $op:block) => {{
         let start = std::time::Instant::now();
         let res = $op;
-        let delta = std::time::Instant::now().duration_since(start);
+        let delta = start.elapsed();
         println!(
             concat!($op_name, " took {} ms"),
             delta.as_secs_f64() * 1000.0

ddtelemetry/src/metrics.rs

@@ -14,10 +14,9 @@ use serde::{Deserialize, Serialize};
 use crate::data::{self, metrics};
 
 fn unix_timestamp_now() -> u64 {
-    time::SystemTime::now()
-        .duration_since(time::SystemTime::UNIX_EPOCH)
-        .map(|d| d.as_secs())
-        .unwrap_or(0)
+    time::SystemTime::UNIX_EPOCH
+        .elapsed()
+        .map_or(0, |d| d.as_secs())
 }
 
 #[derive(Debug)]