From 99ed18350f9572ebb1968107d3708d53682ee805 Mon Sep 17 00:00:00 2001
From: Alex Auvolat <alex@adnab.me>
Date: Thu, 7 Sep 2023 12:41:36 +0200
Subject: [PATCH] block manager: refactor and fix monitoring/statistics

---
 src/block/manager.rs | 47 +++++++++++++++++++-------------------------
 1 file changed, 20 insertions(+), 27 deletions(-)

diff --git a/src/block/manager.rs b/src/block/manager.rs
index eb498be0..0081f46c 100644
--- a/src/block/manager.rs
+++ b/src/block/manager.rs
@@ -491,8 +491,6 @@ impl BlockManager {
 	pub(crate) async fn write_block(&self, hash: &Hash, data: &DataBlock) -> Result<(), Error> {
 		let tracer = opentelemetry::global::tracer("garage");
 
-		let write_size = data.inner_buffer().len() as u64;
-
 		self.lock_mutate(hash)
 			.await
 			.write_block(hash, data, self)
@@ -502,8 +500,6 @@ impl BlockManager {
 			))
 			.await?;
 
-		self.metrics.bytes_written.add(write_size);
-
 		Ok(())
 	}
 
@@ -530,31 +526,26 @@ impl BlockManager {
 
 	/// Read block from disk, verifying it's integrity
 	pub(crate) async fn read_block(&self, hash: &Hash) -> Result<DataBlock, Error> {
-		let data = self
-			.read_block_internal(hash)
-			.bound_record_duration(&self.metrics.block_read_duration)
-			.await?;
-
-		self.metrics
-			.bytes_read
-			.add(data.inner_buffer().len() as u64);
-
-		Ok(data)
-	}
-
-	async fn read_block_internal(&self, hash: &Hash) -> Result<DataBlock, Error> {
-		match self.find_block(hash).await {
-			Some(p) => self.read_block_from(hash, &p).await,
-			None => {
-				// Not found but maybe we should have had it ??
-				self.resync
-					.put_to_resync(hash, 2 * self.system.rpc.rpc_timeout())?;
-				return Err(Error::Message(format!(
-					"block {:?} not found on node",
-					hash
-				)));
+		let tracer = opentelemetry::global::tracer("garage");
+		async {
+			match self.find_block(hash).await {
+				Some(p) => self.read_block_from(hash, &p).await,
+				None => {
+					// Not found but maybe we should have had it ??
+					self.resync
+						.put_to_resync(hash, 2 * self.system.rpc.rpc_timeout())?;
+					return Err(Error::Message(format!(
+						"block {:?} not found on node",
+						hash
+					)));
+				}
 			}
 		}
+		.bound_record_duration(&self.metrics.block_read_duration)
+		.with_context(Context::current_with_span(
+			tracer.start("BlockManager::read_block"),
+		))
+		.await
 	}
 
 	pub(crate) async fn read_block_from(
@@ -570,6 +561,7 @@ impl BlockManager {
 		let mut f = fs::File::open(&path).await?;
 		let mut data = vec![];
 		f.read_to_end(&mut data).await?;
+		self.metrics.bytes_read.add(data.len() as u64);
 		drop(f);
 
 		let data = if compressed {
@@ -731,6 +723,7 @@ impl BlockManagerLocked {
 
 		let mut f = fs::File::create(&path_tmp).await?;
 		f.write_all(data).await?;
+		mgr.metrics.bytes_written.add(data.len() as u64);
 
 		if mgr.data_fsync {
 			f.sync_all().await?;