Add local disk usage to exported prometheus metrics

src/rpc/lib.rs

@@ -3,6 +3,9 @@
 #[macro_use]
 extern crate tracing;
 
+mod metrics;
+mod system_metrics;
+
 #[cfg(feature = "consul-discovery")]
 mod consul;
 #[cfg(feature = "kubernetes-discovery")]
@@ -13,9 +16,6 @@ pub mod replication_mode;
 pub mod ring;
 pub mod system;
 
-mod metrics;
 pub mod rpc_helper;
 
 pub use rpc_helper::*;
-
-pub mod system_metrics;

src/rpc/system.rs

@@ -3,6 +3,7 @@ use std::collections::HashMap;
 use std::io::{Read, Write};
 use std::net::{IpAddr, SocketAddr};
 use std::path::{Path, PathBuf};
+use std::sync::atomic::Ordering;
 use std::sync::{Arc, RwLock};
 use std::time::{Duration, Instant};
 
@@ -38,7 +39,6 @@ use crate::replication_mode::*;
 use crate::ring::*;
 use crate::rpc_helper::*;
 
-#[cfg(feature = "metrics")]
 use crate::system_metrics::*;
 
 const DISCOVERY_INTERVAL: Duration = Duration::from_secs(60);
@@ -106,7 +106,7 @@ pub struct System {
 	consul_discovery: Option<ConsulDiscovery>,
 	#[cfg(feature = "kubernetes-discovery")]
 	kubernetes_discovery: Option<KubernetesDiscoveryConfig>,
-	#[cfg(feature = "metrics")]
+
 	metrics: SystemMetrics,
 
 	replication_mode: ReplicationMode,
@@ -281,12 +281,11 @@ impl System {
 			}
 		};
 
-		let mut local_status = NodeStatus::initial(replication_factor, &cluster_layout);
-		local_status.update_disk_usage(&config.metadata_dir, &config.data_dir);
-
-		#[cfg(feature = "metrics")]
 		let metrics = SystemMetrics::new(replication_factor);
 
+		let mut local_status = NodeStatus::initial(replication_factor, &cluster_layout);
+		local_status.update_disk_usage(&config.metadata_dir, &config.data_dir, &metrics);
+
 		let ring = Ring::new(cluster_layout, replication_factor);
 		let (update_ring, ring) = watch::channel(Arc::new(ring));
 
@@ -377,7 +376,6 @@ impl System {
 			consul_discovery,
 			#[cfg(feature = "kubernetes-discovery")]
 			kubernetes_discovery: config.kubernetes_discovery.clone(),
-			#[cfg(feature = "metrics")]
 			metrics,
 
 			ring,
@@ -601,7 +599,7 @@ impl System {
 		new_si.cluster_layout_version = ring.layout.version;
 		new_si.cluster_layout_staging_hash = ring.layout.staging_hash;
 
-		new_si.update_disk_usage(&self.metadata_dir, &self.data_dir);
+		new_si.update_disk_usage(&self.metadata_dir, &self.data_dir, &self.metrics);
 
 		self.local_status.swap(Arc::new(new_si));
 	}
@@ -892,7 +890,7 @@ impl NodeStatus {
 		}
 	}
 
-	fn update_disk_usage(&mut self, meta_dir: &Path, data_dir: &Path) {
+	fn update_disk_usage(&mut self, meta_dir: &Path, data_dir: &Path, metrics: &SystemMetrics) {
 		use systemstat::{Platform, System};
 		let mounts = System::new().mounts().unwrap_or_default();
 
@@ -906,6 +904,27 @@ impl NodeStatus {
 
 		self.meta_disk_avail = mount_avail(meta_dir);
 		self.data_disk_avail = mount_avail(data_dir);
+
+		if let Some((avail, total)) = self.meta_disk_avail {
+			metrics
+				.values
+				.meta_disk_avail
+				.store(avail, Ordering::Relaxed);
+			metrics
+				.values
+				.meta_disk_total
+				.store(total, Ordering::Relaxed);
+		}
+		if let Some((avail, total)) = self.data_disk_avail {
+			metrics
+				.values
+				.data_disk_avail
+				.store(avail, Ordering::Relaxed);
+			metrics
+				.values
+				.data_disk_total
+				.store(total, Ordering::Relaxed);
+		}
 	}
 }
 

src/rpc/system_metrics.rs

@@ -1,14 +1,31 @@
+use std::sync::atomic::{AtomicU64, Ordering};
+use std::sync::Arc;
+
 use opentelemetry::{global, metrics::*, KeyValue};
 
 /// TableMetrics reference all counter used for metrics
 pub struct SystemMetrics {
 	pub(crate) _garage_build_info: ValueObserver<u64>,
 	pub(crate) _replication_factor: ValueObserver<u64>,
+	pub(crate) _disk_avail: ValueObserver<u64>,
+	pub(crate) _disk_total: ValueObserver<u64>,
+	pub(crate) values: Arc<SystemMetricsValues>,
+}
+
+#[derive(Default)]
+pub struct SystemMetricsValues {
+	pub(crate) data_disk_total: AtomicU64,
+	pub(crate) data_disk_avail: AtomicU64,
+	pub(crate) meta_disk_total: AtomicU64,
+	pub(crate) meta_disk_avail: AtomicU64,
 }
 
 impl SystemMetrics {
 	pub fn new(replication_factor: usize) -> Self {
 		let meter = global::meter("garage_system");
+		let values = Arc::new(SystemMetricsValues::default());
+		let values1 = values.clone();
+		let values2 = values.clone();
 		Self {
 			_garage_build_info: meter
 				.u64_value_observer("garage_build_info", move |observer| {
@@ -28,6 +45,33 @@ impl SystemMetrics {
 				})
 				.with_description("Garage replication factor setting")
 				.init(),
+			_disk_avail: meter
+				.u64_value_observer("garage_local_disk_avail", move |observer| {
+					match values1.data_disk_avail.load(Ordering::Relaxed) {
+						0 => (),
+						x => observer.observe(x, &[KeyValue::new("volume", "data")]),
+					};
+					match values1.meta_disk_avail.load(Ordering::Relaxed) {
+						0 => (),
+						x => observer.observe(x, &[KeyValue::new("volume", "metadata")]),
+					};
+				})
+				.with_description("Garage available disk space on each node")
+				.init(),
+			_disk_total: meter
+				.u64_value_observer("garage_local_disk_total", move |observer| {
+					match values2.data_disk_total.load(Ordering::Relaxed) {
+						0 => (),
+						x => observer.observe(x, &[KeyValue::new("volume", "data")]),
+					};
+					match values2.meta_disk_total.load(Ordering::Relaxed) {
+						0 => (),
+						x => observer.observe(x, &[KeyValue::new("volume", "metadata")]),
+					};
+				})
+				.with_description("Garage total disk space on each node")
+				.init(),
+			values,
 		}
 	}
 }