[Storage] Add a metric to show the latency of k/v read inside put_stats_and_indices. (aptos-labs#3445)

Author: grao1991

storage/aptosdb/src/state_store/mod.rs

@@ -3,8 +3,8 @@
 
 //! This file defines state store APIs that are related account state Merkle tree.
 
-use crate::epoch_by_version::EpochByVersionSchema;
 use crate::{
+    epoch_by_version::EpochByVersionSchema,
     metrics::{STATE_ITEMS, TOTAL_STATE_BYTES},
     schema::state_value::StateValueSchema,
     stale_state_value_index::StaleStateValueIndexSchema,
@@ -490,6 +490,9 @@ impl StateStore {
     }
 
     pub fn get_usage(&self, version: Option<Version>) -> Result<StateStorageUsage> {
+        let _timer = OTHER_TIMERS_SECONDS
+            .with_label_values(&["get_usage"])
+            .start_timer();
         self.state_db.get_state_storage_usage(version)
     }
 
@@ -541,6 +544,9 @@ impl StateStore {
                 {
                     old_value_opt.map(|value| (old_version, value))
                 } else if let Some(base_version) = base_version {
+                    let _timer = OTHER_TIMERS_SECONDS
+                        .with_label_values(&["put_stats_and_indices/get_state_value"])
+                        .start_timer();
                     self.state_db
                         .get_state_value_with_version_by_version(key, base_version)?
                 } else {