feat: Record process metrics (#1646)

* feat(servers): Export process metrics

* chore: update metrics related deps to get the process-metrics printed

The latest process-metrics crate depends on metrics 0.21, we use metrics
0.20. This cause the process-metrics crate doesn't record the metrics
  when use metrics macros

src/common/telemetry/Cargo.toml

@@ -12,8 +12,8 @@ deadlock_detection = ["parking_lot"]
 backtrace = "0.3"
 common-error = { path = "../error" }
 console-subscriber = { version = "0.1", optional = true }
-metrics-exporter-prometheus = { version = "0.11", default-features = false }
-metrics-util = "0.14.0"
+metrics-exporter-prometheus = { version = "0.12", default-features = false }
+metrics-util = "0.15"
 metrics.workspace = true
 once_cell = "1.10"
 opentelemetry = { version = "0.17", default-features = false, features = [

src/object-store/Cargo.toml

@@ -10,7 +10,7 @@ async-trait = "0.1"
 bytes = "1.4"
 futures = { version = "0.3" }
 md5 = "0.7"
-metrics = "0.20"
+metrics.workspace = true
 opendal = { version = "0.33", features = ["layers-tracing", "layers-metrics"] }
 pin-project = "1.0"
 tokio.workspace = true

src/servers/Cargo.toml

@@ -40,6 +40,7 @@ humantime-serde = "1.1"
 hyper = { version = "0.14", features = ["full"] }
 influxdb_line_protocol = { git = "https://github.com/evenyag/influxdb_iox", branch = "feat/line-protocol" }
 metrics.workspace = true
+metrics-process = "1"
 mime_guess = "2.0"
 num_cpus = "1.13"
 once_cell = "1.16"

src/servers/src/http/handler.rs

@@ -26,6 +26,7 @@ use serde::{Deserialize, Serialize};
 use session::context::UserInfo;
 
 use crate::http::{ApiState, JsonResponse};
+use crate::metrics::PROCESS_COLLECTOR;
 use crate::metrics_handler::MetricsHandler;
 
 #[derive(Debug, Default, Serialize, Deserialize, JsonSchema)]
@@ -128,6 +129,9 @@ pub async fn metrics(
     State(state): State<MetricsHandler>,
     Query(_params): Query<HashMap<String, String>>,
 ) -> String {
+    // Collect process metrics.
+    PROCESS_COLLECTOR.collect();
+
     state.render()
 }
 

src/servers/src/metrics.rs

@@ -12,6 +12,9 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
+use metrics_process::Collector;
+use once_cell::sync::Lazy;
+
 pub(crate) const METRIC_DB_LABEL: &str = "db";
 pub(crate) const METRIC_CODE_LABEL: &str = "code";
 
@@ -47,3 +50,11 @@ pub(crate) const METRIC_HTTP_REQUESTS_ELAPSED: &str = "servers.http_requests_ela
 pub(crate) const METRIC_METHOD_LABEL: &str = "method";
 pub(crate) const METRIC_PATH_LABEL: &str = "path";
 pub(crate) const METRIC_STATUS_LABEL: &str = "status";
+
+/// Prometheus style process metrics collector.
+pub(crate) static PROCESS_COLLECTOR: Lazy<Collector> = Lazy::new(|| {
+    let collector = Collector::default();
+    // Describe collector.
+    collector.describe();
+    collector
+});