Partially stablize runtime metrics

.github/workflows/ci.yml

@@ -75,10 +75,18 @@ jobs:
       run: cargo hack check --each-feature --no-dev-deps --all
 
   test-versions:
+    name: test-version (${{ matrix.name }})
     needs: check
     runs-on: ubuntu-latest
+    strategy:
+      matrix:
+        include:
+          - rustflags: "--cfg tokio_unstable -Dwarnings"
+            name: "tokio-unstable"
+          - rustflags: "-Dwarnings"
+            name: "stable"
     env:
-      RUSTFLAGS: --cfg tokio_unstable -Dwarnings
+      RUSTFLAGS: ${{ matrix.rustflags }}
     steps:
     - uses: actions/checkout@master
     - uses: actions-rs/toolchain@v1

Cargo.toml

@@ -26,7 +26,7 @@ rt = ["tokio"]
 tokio-stream = "0.1.11"
 futures-util = "0.3.19"
 pin-project-lite = "0.2.7"
-tokio = { version = "1.41.0", features = ["rt", "time", "net"], optional = true }
+tokio = { version = "1.45.1", features = ["rt", "time", "net"], optional = true }
 metrics = { version = "0.24", optional = true }
 
 [dev-dependencies]
@@ -36,7 +36,7 @@ futures = "0.3.21"
 num_cpus = "1.13.1"
 serde = { version = "1.0.136", features = ["derive"] }
 serde_json = "1.0.79"
-tokio = { version = "1.41.0", features = ["full", "rt", "time", "macros", "test-util"] }
+tokio = { version = "1.45.1", features = ["full", "rt", "time", "macros", "test-util"] }
 metrics-util = { version = "0.19", features = ["debugging"] }
 metrics = { version = "0.24" }
 metrics-exporter-prometheus = { version = "0.16", features = ["uds-listener"] }

README.md

@@ -146,7 +146,7 @@ loop {
 
 ## Getting Started With Runtime Metrics
 
-This unstable functionality requires `tokio_unstable`, and the  `rt` crate
+Not all runtime metrics are stable. Using unstable metrics requires `tokio_unstable`, and the  `rt` crate
 feature. To enable `tokio_unstable`, the `--cfg` `tokio_unstable` must be passed
 to `rustc` when compiling. You can do this by setting the `RUSTFLAGS`
 environment variable before compiling your application; e.g.:
@@ -170,6 +170,17 @@ More information about where cargo looks for configuration files can be found
 Missing this configuration file during compilation will cause tokio-metrics to not work, and alternating
 between building with and without this configuration file included will cause full rebuilds of your project.
 
+### Stable Runtime Metrics
+
+- **[`workers_count`]**
+- **[`total_park_count`]**
+- **[`max_park_count`]**
+- **[`min_park_count`]**
+- **[`total_busy_duration`]**
+- **[`max_busy_duration`]**
+- **[`min_busy_duration`]**
+- **[`global_queue_depth`]**
+
 ### Collecting Runtime Metrics directly
 
 The `rt` feature of `tokio-metrics` is on by default; simply check that you do

examples/axum.rs

@@ -40,9 +40,9 @@ async fn main() {
 
         let intervals = root_intervals.zip(create_user_intervals);
         for (root_route, (create_user_route, create_user_insert)) in intervals {
-            println!("root_route = {:#?}", root_route);
-            println!("create_user_route = {:#?}", create_user_route);
-            println!("create_user_insert = {:#?}", create_user_insert);
+            println!("root_route = {root_route:#?}");
+            println!("create_user_route = {create_user_route:#?}");
+            println!("create_user_insert = {create_user_insert:#?}");
             tokio::time::sleep(metrics_frequency).await;
         }
     });

examples/runtime.rs

@@ -11,7 +11,7 @@ async fn main() -> Result<(), Box<dyn std::error::Error + Send + Sync>> {
         tokio::spawn(async move {
             for interval in runtime_monitor.intervals() {
                 // pretty-print the metric interval
-                println!("{:?}", interval);
+                println!("{interval:?}");
                 // wait 500ms
                 tokio::time::sleep(Duration::from_millis(500)).await;
             }

examples/stream.rs

@@ -12,7 +12,7 @@ async fn main() -> Result<(), Box<dyn std::error::Error + Send + Sync>> {
         tokio::spawn(async move {
             for deltas in metrics_monitor.intervals() {
                 // pretty-print the metric deltas
-                println!("{:?}", deltas);
+                println!("{deltas:?}");
                 // wait 500ms
                 tokio::time::sleep(Duration::from_millis(500)).await;
             }

examples/task.rs

@@ -10,7 +10,7 @@ async fn main() -> Result<(), Box<dyn std::error::Error + Send + Sync>> {
         tokio::spawn(async move {
             for deltas in metrics_monitor.intervals() {
                 // pretty-print the metric deltas
-                println!("{:?}", deltas);
+                println!("{deltas:?}");
                 // wait 500ms
                 tokio::time::sleep(Duration::from_millis(500)).await;
             }

src/lib.rs

@@ -56,11 +56,11 @@
 //! ```
 
 #![cfg_attr(
-    all(tokio_unstable, feature = "rt"),
+    feature = "rt",
     doc = r##"
-### Monitoring runtime metrics (unstable)
+### Monitoring runtime metrics
 [Monitor][RuntimeMonitor] key [metrics][RuntimeMetrics] of a tokio runtime.
-**This functionality requires `tokio_unstable` and the crate feature `rt`.**
+**This functionality requires crate feature `rt` and some metrics require `tokio_unstable`.**
 
 In the below example, a [`RuntimeMonitor`] is [constructed][RuntimeMonitor::new] and
 three tasks are spawned and awaited; meanwhile, a fourth task prints [metrics][RuntimeMetrics]
@@ -104,7 +104,7 @@ async fn do_work() {
 }
 ```
 
-### Monitoring and publishing runtime metrics (unstable)
+### Monitoring and publishing runtime metrics
 
 If the `metrics-rs-integration` feature is additionally enabled, this crate allows
 publishing runtime metrics externally via [metrics-rs](metrics) exporters.
@@ -156,8 +156,8 @@ async fn main() {
 macro_rules! cfg_rt {
     ($($item:item)*) => {
         $(
-            #[cfg(all(tokio_unstable, feature = "rt"))]
-            #[cfg_attr(docsrs, doc(cfg(all(tokio_unstable, feature = "rt"))))]
+            #[cfg(feature = "rt")]
+            #[cfg_attr(docsrs, doc(cfg(feature = "rt")))]
             $item
         )*
     };
@@ -172,10 +172,10 @@ cfg_rt! {
     };
 }
 
-#[cfg(all(tokio_unstable, feature = "rt", feature = "metrics-rs-integration"))]
+#[cfg(all(feature = "rt", feature = "metrics-rs-integration"))]
 #[cfg_attr(
     docsrs,
-    doc(cfg(all(tokio_unstable, feature = "rt", feature = "metrics-rs-integration")))
+    doc(cfg(all(feature = "rt", feature = "metrics-rs-integration")))
 )]
 pub use runtime::metrics_rs_integration::{RuntimeMetricsReporter, RuntimeMetricsReporterBuilder};