State metrics possible changes (#5168)

* Registering state from overlay.

* fix

* fix2

* Apply suggestions from code review

Co-authored-by: Bastian Köcher <bkchr@users.noreply.github.com>

substrate/primitives/state-machine/src/stats.rs

@@ -17,6 +17,7 @@
 //! Usage statistics for state db
 
 use std::time::{Instant, Duration};
+use std::cell::RefCell;
 
 /// Measured count of operations and total bytes.
 #[derive(Clone, Debug, Default)]
@@ -32,10 +33,19 @@ pub struct UsageUnit {
 pub struct UsageInfo {
 	/// Read statistics (total).
 	pub reads: UsageUnit,
-	/// Write statistics.
+	/// Write statistics (total).
 	pub writes: UsageUnit,
+	/// Write trie nodes statistics.
+	pub nodes_writes: UsageUnit,
+	/// Write into cached state machine
+	/// change overlay.
+	pub overlay_writes: UsageUnit,
+	/// Removed trie nodes statistics.
+	pub removed_nodes: UsageUnit,
 	/// Cache read statistics.
 	pub cache_reads: UsageUnit,
+	/// Modified value read statistics.
+	pub modified_reads: UsageUnit,
 	/// Memory used.
 	pub memory: usize,
 
@@ -45,6 +55,35 @@ pub struct UsageInfo {
 	pub span: Duration,
 }
 
+/// Accumulated usage statistics specific to state machine
+/// crate.
+#[derive(Debug, Default, Clone)]
+pub struct StateMachineStats {
+	/// Number of read query from runtime
+	/// that hit a modified value (in state
+	/// machine overlay).
+	pub reads_modified: RefCell<u64>,
+	/// Size in byte of read queries that
+	/// hit a modified value.
+	pub bytes_read_modified: RefCell<u64>,
+	/// Number of time a write operation
+	/// occurs into the state machine overlay.
+	pub writes_overlay: RefCell<u64>,
+	/// Size in bytes of the writes overlay
+	/// operation.
+	pub bytes_writes_overlay: RefCell<u64>,
+}
+
+impl StateMachineStats {
+	/// Accumulates some registered stats.
+	pub fn add(&self, other: &StateMachineStats) {
+		*self.reads_modified.borrow_mut() += *other.reads_modified.borrow();
+		*self.bytes_read_modified.borrow_mut() += *other.bytes_read_modified.borrow();
+		*self.writes_overlay.borrow_mut() += *other.writes_overlay.borrow();
+		*self.bytes_writes_overlay.borrow_mut() += *other.bytes_writes_overlay.borrow();
+	}
+}
+
 impl UsageInfo {
 	/// Empty statistics.
 	///
@@ -53,10 +92,34 @@ impl UsageInfo {
 		Self {
 			reads: UsageUnit::default(),
 			writes: UsageUnit::default(),
+			overlay_writes: UsageUnit::default(),
+			nodes_writes: UsageUnit::default(),
+			removed_nodes: UsageUnit::default(),
 			cache_reads: UsageUnit::default(),
+			modified_reads: UsageUnit::default(),
 			memory: 0,
 			started: Instant::now(),
 			span: Default::default(),
 		}
 	}
+	/// Add collected state machine to this state.
+	pub fn include_state_machine_states(&mut self, count: &StateMachineStats) {
+		self.modified_reads.ops += *count.reads_modified.borrow();
+		self.modified_reads.bytes += *count.bytes_read_modified.borrow();
+		self.overlay_writes.ops += *count.writes_overlay.borrow();
+		self.overlay_writes.bytes += *count.bytes_writes_overlay.borrow();
+	}
+}
+
+impl StateMachineStats {
+	/// Tally one read modified operation, of some length.
+	pub fn tally_read_modified(&self, data_bytes: u64) {
+		*self.reads_modified.borrow_mut() += 1;
+		*self.bytes_read_modified.borrow_mut() += data_bytes;
+	}
+	/// Tally one write overlay operation, of some length.
+	pub fn tally_write_overlay(&self, data_bytes: u64) {
+		*self.writes_overlay.borrow_mut() += 1;
+		*self.bytes_writes_overlay.borrow_mut() += data_bytes;
+	}
 }