feat: Add logging & metrics for mempool (#3447)

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lint`.

core/lib/dal/src/transactions_dal.rs

@@ -1776,7 +1776,7 @@ impl TransactionsDal<'_, '_> {
         limit: usize,
     ) -> DalResult<Vec<(Transaction, TransactionTimeRangeConstraint)>> {
         let stashed_addresses: Vec<_> = stashed_accounts.iter().map(Address::as_bytes).collect();
-        sqlx::query!(
+        let result = sqlx::query!(
             r#"
             UPDATE transactions
             SET
@@ -1794,8 +1794,15 @@ impl TransactionsDal<'_, '_> {
         .execute(self.storage)
         .await?;
 
+        tracing::debug!(
+            "Updated {} transactions for stashed accounts, stashed accounts amount: {}, stashed_accounts: {:?}",
+            result.rows_affected(),
+            stashed_addresses.len(),
+            stashed_accounts.iter().map(|a|format!("{:x}", a)).collect::<Vec<_>>()
+        );
+
         let purged_addresses: Vec<_> = purged_accounts.iter().map(Address::as_bytes).collect();
-        sqlx::query!(
+        let result = sqlx::query!(
             r#"
             DELETE FROM transactions
             WHERE
@@ -1809,6 +1816,12 @@ impl TransactionsDal<'_, '_> {
         .execute(self.storage)
         .await?;
 
+        tracing::debug!(
+            "Updated {} transactions for purged accounts, purged accounts amount: {}",
+            result.rows_affected(),
+            purged_addresses.len()
+        );
+
         // Note, that transactions are updated in order of their hashes to avoid deadlocks with other UPDATE queries.
         let transactions = sqlx::query_as!(
             StorageTransaction,

core/lib/mempool/src/mempool_store.rs

@@ -172,6 +172,8 @@ impl MempoolStore {
             .rfind(|el| el.matches_filter(filter))?
             .clone();
 
+        let initial_length = self.stashed_accounts.len();
+
         // Stash all observed transactions that don't meet criteria
         for stashed_pointer in self
             .l2_priority_queue
@@ -187,6 +189,13 @@ impl MempoolStore {
 
             self.stashed_accounts.push(stashed_pointer.account);
         }
+
+        tracing::debug!(
+            "Stashed {} accounts by filter: {:?}",
+            self.stashed_accounts.len() - initial_length,
+            filter
+        );
+
         // insert pointer to the next transaction if it exists
         let (transaction, constraint, score) = self
             .l2_transactions_per_account

core/node/state_keeper/src/mempool_actor.rs

@@ -83,6 +83,14 @@ impl MempoolFetcher {
             let latency = KEEPER_METRICS.mempool_sync.start();
             let mut storage = self.pool.connection_tagged("state_keeper").await?;
             let mempool_info = self.mempool.get_mempool_info();
+
+            KEEPER_METRICS
+                .mempool_stashed_accounts
+                .set(mempool_info.stashed_accounts.len());
+            KEEPER_METRICS
+                .mempool_purged_accounts
+                .set(mempool_info.purged_accounts.len());
+
             let protocol_version = storage
                 .blocks_dal()
                 .pending_protocol_version()

core/node/state_keeper/src/metrics.rs

@@ -64,6 +64,10 @@ pub struct StateKeeperMetrics {
     /// Latency to synchronize the mempool with Postgres.
     #[metrics(buckets = Buckets::LATENCIES)]
     pub mempool_sync: Histogram<Duration>,
+    /// Number of stashed accounts in mempool
+    pub mempool_stashed_accounts: Gauge<usize>,
+    /// Number of purged accounts in mempool
+    pub mempool_purged_accounts: Gauge<usize>,
     /// Latency of the state keeper waiting for a transaction.
     #[metrics(buckets = Buckets::LATENCIES)]
     pub waiting_for_tx: Histogram<Duration>,