Disk space report

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

3 files changed, 126 insertions, 19 deletions

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)]