Disk space report

Report available disk space on nodes and calculate cluster-wide available space in `garage stats` (fix #479)

8 files changed, 220 insertions, 35 deletions

diff --git a/Cargo.lock b/Cargo.lock
index 5d38b92a..871d897f 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -1230,6 +1230,7 @@ dependencies = [
  "serde",
  "serde_bytes",
  "serde_json",
+ "systemstat",
  "tokio",
  "tokio-stream",
  "tracing",
@@ -3568,6 +3569,20 @@ dependencies = [
 ]
 
 [[package]]
+name = "systemstat"
+version = "0.2.3"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "a24aec24a9312c83999a28e3ef9db7e2afd5c64bf47725b758cdc1cafd5b0bd2"
+dependencies = [
+ "bytesize",
+ "lazy_static",
+ "libc",
+ "nom",
+ "time 0.3.9",
+ "winapi",
+]
+
+[[package]]
 name = "tempfile"
 version = "3.3.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
diff --git a/Cargo.nix b/Cargo.nix
index 9ee5b9fb..24c09e92 100644
--- a/Cargo.nix
+++ b/Cargo.nix
@@ -32,7 +32,7 @@ args@{
   ignoreLockHash,
 }:
 let
-  nixifiedLockHash = "8461dcfb984a8d042fecb5745d5da17912135dbf2a8ef7e6c3ae8e64c03d9744";
+  nixifiedLockHash = "e59ef222aaaada125e2a5fccbd215b545740b2abd21ce381c42a7a6e3a7e672a";
   workspaceSrc = if args.workspaceSrc == null then ./. else args.workspaceSrc;
   currentLockHash = builtins.hashFile "sha256" (workspaceSrc + /Cargo.lock);
   lockHashIgnored = if ignoreLockHash
@@ -1753,6 +1753,7 @@ in
       serde = (rustPackages."registry+https://github.com/rust-lang/crates.io-index".serde."1.0.137" { inherit profileName; }).out;
       serde_bytes = (rustPackages."registry+https://github.com/rust-lang/crates.io-index".serde_bytes."0.11.5" { inherit profileName; }).out;
       serde_json = (rustPackages."registry+https://github.com/rust-lang/crates.io-index".serde_json."1.0.81" { inherit profileName; }).out;
+      systemstat = (rustPackages."registry+https://github.com/rust-lang/crates.io-index".systemstat."0.2.3" { inherit profileName; }).out;
       tokio = (rustPackages."registry+https://github.com/rust-lang/crates.io-index".tokio."1.17.0" { inherit profileName; }).out;
       tokio_stream = (rustPackages."registry+https://github.com/rust-lang/crates.io-index".tokio-stream."0.1.8" { inherit profileName; }).out;
       tracing = (rustPackages."registry+https://github.com/rust-lang/crates.io-index".tracing."0.1.32" { inherit profileName; }).out;
@@ -4917,6 +4918,21 @@ in
     };
   });
   
+  "registry+https://github.com/rust-lang/crates.io-index".systemstat."0.2.3" = overridableMkRustCrate (profileName: rec {
+    name = "systemstat";
+    version = "0.2.3";
+    registry = "registry+https://github.com/rust-lang/crates.io-index";
+    src = fetchCratesIo { inherit name version; sha256 = "a24aec24a9312c83999a28e3ef9db7e2afd5c64bf47725b758cdc1cafd5b0bd2"; };
+    dependencies = {
+      bytesize = (rustPackages."registry+https://github.com/rust-lang/crates.io-index".bytesize."1.1.0" { inherit profileName; }).out;
+      lazy_static = (rustPackages."registry+https://github.com/rust-lang/crates.io-index".lazy_static."1.4.0" { inherit profileName; }).out;
+      libc = (rustPackages."registry+https://github.com/rust-lang/crates.io-index".libc."0.2.121" { inherit profileName; }).out;
+      ${ if hostPlatform.parsed.kernel.name == "linux" || hostPlatform.parsed.kernel.name == "android" then "nom" else null } = (rustPackages."registry+https://github.com/rust-lang/crates.io-index".nom."7.1.1" { inherit profileName; }).out;
+      time = (rustPackages."registry+https://github.com/rust-lang/crates.io-index".time."0.3.9" { inherit profileName; }).out;
+      ${ if hostPlatform.isWindows then "winapi" else null } = (rustPackages."registry+https://github.com/rust-lang/crates.io-index".winapi."0.3.9" { inherit profileName; }).out;
+    };
+  });
+  
   "registry+https://github.com/rust-lang/crates.io-index".tempfile."3.3.0" = overridableMkRustCrate (profileName: rec {
     name = "tempfile";
     version = "3.3.0";
@@ -5890,6 +5906,7 @@ in
       [ "ntsecapi" ]
       [ "ntstatus" ]
       [ "objbase" ]
+      [ "pdh" ]
       [ "processenv" ]
       [ "processthreadsapi" ]
       [ "profileapi" ]
diff --git a/Makefile b/Makefile
index 23e10f78..55fa16dd 100644
--- a/Makefile
+++ b/Makefile
@@ -4,7 +4,7 @@ all:
 	clear; cargo build
 
 release:
-	nix-build --arg release true
+	nix-build --attr pkgs.amd64.release --no-build-output
 
 shell:
 	nix-shell
diff --git a/src/garage/admin.rs b/src/garage/admin.rs
index 305c5c65..4eabebca 100644
--- a/src/garage/admin.rs
+++ b/src/garage/admin.rs
@@ -15,6 +15,7 @@ use garage_util::time::*;
 use garage_table::replication::*;
 use garage_table::*;
 
+use garage_rpc::ring::PARTITION_BITS;
 use garage_rpc::*;
 
 use garage_block::manager::BlockResyncErrorInfo;
@@ -783,6 +784,7 @@ impl AdminRpcHandler {
 			for node in ring.layout.node_ids().iter() {
 				let mut opt = opt.clone();
 				opt.all_nodes = false;
+				opt.skip_global = true;
 
 				writeln!(&mut ret, "\n======================").unwrap();
 				writeln!(&mut ret, "Stats for node {:?}:", node).unwrap();
@@ -799,6 +801,15 @@ impl AdminRpcHandler {
 					Err(e) => writeln!(&mut ret, "Network error: {}", e).unwrap(),
 				}
 			}
+
+			writeln!(&mut ret, "\n======================").unwrap();
+			write!(
+				&mut ret,
+				"Cluster statistics:\n\n{}",
+				self.gather_cluster_stats()
+			)
+			.unwrap();
+
 			Ok(AdminRpc::Ok(ret))
 		} else {
 			Ok(AdminRpc::Ok(self.gather_stats_local(opt)?))
@@ -819,22 +830,6 @@ impl AdminRpcHandler {
 
 		writeln!(&mut ret, "\nDatabase engine: {}", self.garage.db.engine()).unwrap();
 
-		// Gather ring statistics
-		let ring = self.garage.system.ring.borrow().clone();
-		let mut ring_nodes = HashMap::new();
-		for (_i, loc) in ring.partitions().iter() {
-			for n in ring.get_nodes(loc, ring.replication_factor).iter() {
-				if !ring_nodes.contains_key(n) {
-					ring_nodes.insert(*n, 0usize);
-				}
-				*ring_nodes.get_mut(n).unwrap() += 1;
-			}
-		}
-		writeln!(&mut ret, "\nRing nodes & partition count:").unwrap();
-		for (n, c) in ring_nodes.iter() {
-			writeln!(&mut ret, "  {:?} {}", n, c).unwrap();
-		}
-
 		// Gather table statistics
 		let mut table = vec!["  Table\tItems\tMklItems\tMklTodo\tGcTodo".into()];
 		table.push(self.gather_table_stats(&self.garage.bucket_table, opt.detailed)?);
@@ -881,12 +876,108 @@ impl AdminRpcHandler {
 		.unwrap();
 
 		if !opt.detailed {
-			writeln!(&mut ret, "\nIf values are missing (marked as NC), consider adding the --detailed flag - this will be slow.").unwrap();
+			writeln!(&mut ret, "\nIf values are missing above (marked as NC), consider adding the --detailed flag (this will be slow).").unwrap();
+		}
+
+		if !opt.skip_global {
+			write!(&mut ret, "\n{}", self.gather_cluster_stats()).unwrap();
 		}
 
 		Ok(ret)
 	}
 
+	fn gather_cluster_stats(&self) -> String {
+		let mut ret = String::new();
+
+		// Gather storage node and free space statistics
+		let layout = &self.garage.system.ring.borrow().layout;
+		let mut node_partition_count = HashMap::<Uuid, u64>::new();
+		for short_id in layout.ring_assignation_data.iter() {
+			let id = layout.node_id_vec[*short_id as usize];
+			*node_partition_count.entry(id).or_default() += 1;
+		}
+		let node_info = self
+			.garage
+			.system
+			.get_known_nodes()
+			.into_iter()
+			.map(|n| (n.id, n))
+			.collect::<HashMap<_, _>>();
+
+		let mut table = vec!["  ID\tHostname\tZone\tCapacity\tPart.\tDataAvail\tMetaAvail".into()];
+		for (id, parts) in node_partition_count.iter() {
+			let info = node_info.get(id);
+			let status = info.map(|x| &x.status);
+			let role = layout.roles.get(id).and_then(|x| x.0.as_ref());
+			let hostname = status.map(|x| x.hostname.as_str()).unwrap_or("?");
+			let zone = role.map(|x| x.zone.as_str()).unwrap_or("?");
+			let capacity = role.map(|x| x.capacity_string()).unwrap_or("?".into());
+			let avail_str = |x| match x {
+				Some((avail, total)) => {
+					let pct = (avail as f64) / (total as f64) * 100.;
+					let avail = bytesize::ByteSize::b(avail);
+					let total = bytesize::ByteSize::b(total);
+					format!("{}/{} ({:.1}%)", avail, total, pct)
+				}
+				None => "?".into(),
+			};
+			let data_avail = avail_str(status.and_then(|x| x.data_disk_avail));
+			let meta_avail = avail_str(status.and_then(|x| x.meta_disk_avail));
+			table.push(format!(
+				"  {:?}\t{}\t{}\t{}\t{}\t{}\t{}",
+				id, hostname, zone, capacity, parts, data_avail, meta_avail
+			));
+		}
+		write!(
+			&mut ret,
+			"Storage nodes:\n{}",
+			format_table_to_string(table)
+		)
+		.unwrap();
+
+		let meta_part_avail = node_partition_count
+			.iter()
+			.filter_map(|(id, parts)| {
+				node_info
+					.get(id)
+					.and_then(|x| x.status.meta_disk_avail)
+					.map(|c| c.0 / *parts)
+			})
+			.collect::<Vec<_>>();
+		let data_part_avail = node_partition_count
+			.iter()
+			.filter_map(|(id, parts)| {
+				node_info
+					.get(id)
+					.and_then(|x| x.status.data_disk_avail)
+					.map(|c| c.0 / *parts)
+			})
+			.collect::<Vec<_>>();
+		if !meta_part_avail.is_empty() && !data_part_avail.is_empty() {
+			let meta_avail =
+				bytesize::ByteSize(meta_part_avail.iter().min().unwrap() * (1 << PARTITION_BITS));
+			let data_avail =
+				bytesize::ByteSize(data_part_avail.iter().min().unwrap() * (1 << PARTITION_BITS));
+			writeln!(
+				&mut ret,
+				"\nEstimated available storage space cluster-wide (might be lower in practice):"
+			)
+			.unwrap();
+			if meta_part_avail.len() < node_partition_count.len()
+				|| data_part_avail.len() < node_partition_count.len()
+			{
+				writeln!(&mut ret, "  data: < {}", data_avail).unwrap();
+				writeln!(&mut ret, "  metadata: < {}", meta_avail).unwrap();
+				writeln!(&mut ret, "A precise estimate could not be given as information is missing for some storage nodes.").unwrap();
+			} else {
+				writeln!(&mut ret, "  data: {}", data_avail).unwrap();
+				writeln!(&mut ret, "  metadata: {}", meta_avail).unwrap();
+			}
+		}
+
+		ret
+	}
+
 	fn gather_table_stats<F, R>(
 		&self,
 		t: &Arc<Table<F, R>>,
diff --git a/src/garage/cli/cmd.rs b/src/garage/cli/cmd.rs
index 46e9113c..af7f1aa1 100644
--- a/src/garage/cli/cmd.rs
+++ b/src/garage/cli/cmd.rs
@@ -59,18 +59,29 @@ pub async fn cmd_status(rpc_cli: &Endpoint<SystemRpc, ()>, rpc_host: NodeID) ->
 	let layout = fetch_layout(rpc_cli, rpc_host).await?;
 
 	println!("==== HEALTHY NODES ====");
-	let mut healthy_nodes = vec!["ID\tHostname\tAddress\tTags\tZone\tCapacity".to_string()];
+	let mut healthy_nodes =
+		vec!["ID\tHostname\tAddress\tTags\tZone\tCapacity\tDataAvail\tMetaAvail".to_string()];
 	for adv in status.iter().filter(|adv| adv.is_up) {
 		match layout.roles.get(&adv.id) {
 			Some(NodeRoleV(Some(cfg))) => {
+				let data_avail = match &adv.status.data_disk_avail {
+					_ if cfg.capacity.is_none() => "N/A".into(),
+					Some((avail, total)) => {
+						let pct = (*avail as f64) / (*total as f64) * 100.;
+						let avail = bytesize::ByteSize::b(*avail);
+						format!("{} ({:.1}%)", avail, pct)
+					}
+					None => "?".into(),
+				};
 				healthy_nodes.push(format!(
-					"{id:?}\t{host}\t{addr}\t[{tags}]\t{zone}\t{capacity}",
+					"{id:?}\t{host}\t{addr}\t[{tags}]\t{zone}\t{capacity}\t{data_avail}",
 					id = adv.id,
 					host = adv.status.hostname,
 					addr = adv.addr,
 					tags = cfg.tags.join(","),
 					zone = cfg.zone,
 					capacity = cfg.capacity_string(),
+					data_avail = data_avail,
 				));
 			}
 			_ => {
diff --git a/src/garage/cli/structs.rs b/src/garage/cli/structs.rs
index 661a71f0..01ae92da 100644
--- a/src/garage/cli/structs.rs
+++ b/src/garage/cli/structs.rs
@@ -504,6 +504,11 @@ pub struct StatsOpt {
 	/// Gather detailed statistics (this can be long)
 	#[structopt(short = "d", long = "detailed")]
 	pub detailed: bool,
+
+	/// Don't show global cluster stats (internal use in RPC)
+	#[structopt(skip)]
+	#[serde(default)]
+	pub skip_global: bool,
 }
 
 #[derive(Serialize, Deserialize, StructOpt, Debug, Eq, PartialEq, Clone)]
diff --git a/src/rpc/Cargo.toml b/src/rpc/Cargo.toml
index e9a0929a..2daa0176 100644
--- a/src/rpc/Cargo.toml
+++ b/src/rpc/Cargo.toml
@@ -23,6 +23,7 @@ hex = "0.4"
 tracing = "0.1.30"
 rand = "0.8"
 sodiumoxide = { version = "0.2.5-0", package = "kuska-sodiumoxide" }
+systemstat = "0.2.3"
 
 async-trait = "0.1.7"
 serde = { version = "1.0", default-features = false, features = ["derive", "rc"] }
diff --git a/src/rpc/system.rs b/src/rpc/system.rs
index 90f6a4c2..a9e91e19 100644
--- a/src/rpc/system.rs
+++ b/src/rpc/system.rs
@@ -118,18 +118,28 @@ pub struct System {
 
 	/// Path to metadata directory
 	pub metadata_dir: PathBuf,
+	/// Path to data directory
+	pub data_dir: PathBuf,
 }
 
 #[derive(Debug, Clone, Serialize, Deserialize)]
 pub struct NodeStatus {
 	/// Hostname of the node
 	pub hostname: String,
+
 	/// Replication factor configured on the node
 	pub replication_factor: usize,
 	/// Cluster layout version
 	pub cluster_layout_version: u64,
 	/// Hash of cluster layout staging data
 	pub cluster_layout_staging_hash: Hash,
+
+	/// Disk usage on partition containing metadata directory (tuple: `(avail, total)`)
+	#[serde(default)]
+	pub meta_disk_avail: Option<(u64, u64)>,
+	/// Disk usage on partition containing data directory (tuple: `(avail, total)`)
+	#[serde(default)]
+	pub data_disk_avail: Option<(u64, u64)>,
 }
 
 #[derive(Debug, Clone, Serialize, Deserialize)]
@@ -271,14 +281,8 @@ impl System {
 			}
 		};
 
-		let local_status = NodeStatus {
-			hostname: gethostname::gethostname()
-				.into_string()
-				.unwrap_or_else(|_| "<invalid utf-8>".to_string()),
-			replication_factor,
-			cluster_layout_version: cluster_layout.version,
-			cluster_layout_staging_hash: cluster_layout.staging_hash,
-		};
+		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);
@@ -379,6 +383,7 @@ impl System {
 			ring,
 			update_ring: Mutex::new(update_ring),
 			metadata_dir: config.metadata_dir.clone(),
+			data_dir: config.data_dir.clone(),
 		});
 		sys.system_endpoint.set_handler(sys.clone());
 		Ok(sys)
@@ -416,12 +421,7 @@ impl System {
 					.get(&n.id.into())
 					.cloned()
 					.map(|(_, st)| st)
-					.unwrap_or(NodeStatus {
-						hostname: "?".to_string(),
-						replication_factor: 0,
-						cluster_layout_version: 0,
-						cluster_layout_staging_hash: Hash::from([0u8; 32]),
-					}),
+					.unwrap_or(NodeStatus::unknown()),
 			})
 			.collect::<Vec<_>>();
 		known_nodes
@@ -600,6 +600,9 @@ impl System {
 		let ring = self.ring.borrow();
 		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);
+
 		self.local_status.swap(Arc::new(new_si));
 	}
 
@@ -864,6 +867,48 @@ impl EndpointHandler<SystemRpc> for System {
 	}
 }
 
+impl NodeStatus {
+	fn initial(replication_factor: usize, layout: &ClusterLayout) -> Self {
+		NodeStatus {
+			hostname: gethostname::gethostname()
+				.into_string()
+				.unwrap_or_else(|_| "<invalid utf-8>".to_string()),
+			replication_factor,
+			cluster_layout_version: layout.version,
+			cluster_layout_staging_hash: layout.staging_hash,
+			meta_disk_avail: None,
+			data_disk_avail: None,
+		}
+	}
+
+	fn unknown() -> Self {
+		NodeStatus {
+			hostname: "?".to_string(),
+			replication_factor: 0,
+			cluster_layout_version: 0,
+			cluster_layout_staging_hash: Hash::from([0u8; 32]),
+			meta_disk_avail: None,
+			data_disk_avail: None,
+		}
+	}
+
+	fn update_disk_usage(&mut self, meta_dir: &Path, data_dir: &Path) {
+		use systemstat::{Platform, System};
+		let mounts = System::new().mounts().unwrap_or_default();
+
+		let mount_avail = |path: &Path| {
+			mounts
+				.iter()
+				.filter(|x| path.starts_with(&x.fs_mounted_on))
+				.max_by_key(|x| x.fs_mounted_on.len())
+				.map(|x| (x.avail.as_u64(), x.total.as_u64()))
+		};
+
+		self.meta_disk_avail = mount_avail(meta_dir);
+		self.data_disk_avail = mount_avail(data_dir);
+	}
+}
+
 fn get_default_ip() -> Option<IpAddr> {
 	pnet_datalink::interfaces()
 		.iter()