refactor(531): Label transaction count metric with boolean flag

Fixes #531.

Instead of having two distinct metrics for commits and rollbacks,
this patch replaces them with a single metric plus a boolean label
representing whether the transaction was committed or rolled back.

crates/core/src/db/datastore/locking_tx_datastore/mod.rs

@@ -2115,39 +2115,45 @@ impl traits::MutTx for Locking {
     }
 
     fn rollback_mut_tx(&self, ctx: &ExecutionContext, mut tx: Self::MutTxId) {
+        let txn_type = &ctx.txn_type();
+        let db = &ctx.database();
+        let reducer = ctx.reducer_name().unwrap_or_default();
         let elapsed_time = tx.timer.elapsed();
         let cpu_time = elapsed_time - tx.lock_wait_time;
         DB_METRICS
-            .rdb_num_txns_rolledback
-            .with_label_values(&ctx.txn_type(), &ctx.database(), ctx.reducer_name().unwrap_or(""))
+            .rdb_num_txns
+            .with_label_values(txn_type, db, reducer, &false)
             .inc();
         DB_METRICS
             .rdb_txn_cpu_time_sec
-            .with_label_values(&ctx.txn_type(), &ctx.database(), ctx.reducer_name().unwrap_or(""))
+            .with_label_values(txn_type, db, reducer)
             .observe(cpu_time.as_secs_f64());
         DB_METRICS
             .rdb_txn_elapsed_time_sec
-            .with_label_values(&ctx.txn_type(), &ctx.database(), ctx.reducer_name().unwrap_or(""))
+            .with_label_values(txn_type, db, reducer)
             .observe(elapsed_time.as_secs_f64());
         tx.lock.rollback();
     }
 
     fn commit_mut_tx(&self, ctx: &ExecutionContext, mut tx: Self::MutTxId) -> super::Result<Option<TxData>> {
+        let txn_type = &ctx.txn_type();
+        let db = &ctx.database();
+        let reducer = ctx.reducer_name().unwrap_or_default();
         let elapsed_time = tx.timer.elapsed();
         let cpu_time = elapsed_time - tx.lock_wait_time;
         // Note, we record empty transactions in our metrics.
         // That is, transactions that don't write any rows to the commit log.
         DB_METRICS
-            .rdb_num_txns_committed
-            .with_label_values(&ctx.txn_type(), &ctx.database(), ctx.reducer_name().unwrap_or(""))
+            .rdb_num_txns
+            .with_label_values(txn_type, db, reducer, &true)
             .inc();
         DB_METRICS
             .rdb_txn_cpu_time_sec
-            .with_label_values(&ctx.txn_type(), &ctx.database(), ctx.reducer_name().unwrap_or(""))
+            .with_label_values(txn_type, db, reducer)
             .observe(cpu_time.as_secs_f64());
         DB_METRICS
             .rdb_txn_elapsed_time_sec
-            .with_label_values(&ctx.txn_type(), &ctx.database(), ctx.reducer_name().unwrap_or(""))
+            .with_label_values(txn_type, db, reducer)
             .observe(elapsed_time.as_secs_f64());
         tx.lock.commit()
     }

crates/core/src/db/db_metrics/mod.rs

@@ -86,15 +86,10 @@ metrics_group!(
         #[labels(txn_type: TransactionType, db: Address, reducer: str, table_id: u32)]
         pub rdb_num_index_seeks: IntCounterVec,
 
-        #[name = spacetime_num_txns_committed_cumulative]
-        #[help = "The cumulative number of committed transactions"]
-        #[labels(txn_type: TransactionType, db: Address, reducer: str)]
-        pub rdb_num_txns_committed: IntCounterVec,
-
-        #[name = spacetime_num_txns_rolledback_cumulative]
-        #[help = "The cumulative number of rolled back transactions"]
-        #[labels(txn_type: TransactionType, db: Address, reducer: str)]
-        pub rdb_num_txns_rolledback: IntCounterVec,
+        #[name = spacetime_num_txns_cumulative]
+        #[help = "The cumulative number of transactions, both commits and rollbacks"]
+        #[labels(txn_type: TransactionType, db: Address, reducer: str, committed: bool)]
+        pub rdb_num_txns: IntCounterVec,
 
         #[name = spacetime_txn_elapsed_time_sec]
         #[help = "The total elapsed (wall) time of a transaction (in seconds)"]

crates/core/src/util/typed_prometheus.rs

@@ -122,6 +122,7 @@ impl_prometheusvalue_string!(
     Address,
     TransactionType,
     AbiCall,
+    bool,
     u8,
     u16,
     u32,