refactor(metrics): Move table size metric into lib

Query optimization will soon need this metric.
Therefore it must be moved out of core and into lib.
Eventually we might want to move all metrics into lib.

Author: joshua-spacetime

Cargo.lock

@@ -18,6 +18,7 @@ use crate::{
     execution_context::ExecutionContext,
 };
 use anyhow::Context;
+use spacetimedb_lib::metrics::METRICS;
 use spacetimedb_sats::hash::{hash_bytes, Hash};
 use spacetimedb_sats::DataKey;
 use std::{
@@ -380,7 +381,7 @@ impl CommitLogMut {
                         .with_label_values(workload, db, reducer_or_query, &table_id)
                         .inc();
                     // Increment table rows gauge
-                    DB_METRICS.rdb_num_table_rows.with_label_values(db, &table_id).inc();
+                    METRICS.rdb_num_table_rows.with_label_values(db, &table_id).inc();
                     Operation::Insert
                 }
                 TxOp::Delete => {
@@ -390,7 +391,7 @@ impl CommitLogMut {
                         .with_label_values(workload, db, reducer_or_query, &table_id)
                         .inc();
                     // Decrement table rows gauge
-                    DB_METRICS.rdb_num_table_rows.with_label_values(db, &table_id).dec();
+                    METRICS.rdb_num_table_rows.with_label_values(db, &table_id).dec();
                     Operation::Delete
                 }
             };

crates/core/src/db/commit_log.rs

@@ -48,7 +48,7 @@ use crate::{
 };
 use anyhow::anyhow;
 use parking_lot::{lock_api::ArcRwLockWriteGuard, RawRwLock, RwLock};
-use spacetimedb_lib::Address;
+use spacetimedb_lib::{metrics::METRICS, Address};
 use spacetimedb_primitives::*;
 use spacetimedb_sats::data_key::{DataKey, ToDataKey};
 use spacetimedb_sats::db::def::*;
@@ -250,7 +250,7 @@ impl CommittedState {
         for schema in system_tables() {
             let table_id = schema.table_id;
             // Reset the row count metric for this system table
-            DB_METRICS
+            METRICS
                 .rdb_num_table_rows
                 .with_label_values(&database_address, &table_id.0)
                 .set(0);
@@ -283,7 +283,7 @@ impl CommittedState {
 
             st_columns.rows.insert(RowId(data_key), row);
             // Increment row count for st_columns
-            DB_METRICS
+            METRICS
                 .rdb_num_table_rows
                 .with_label_values(&database_address, &ST_COLUMNS_ID.into())
                 .inc();
@@ -311,7 +311,7 @@ impl CommittedState {
             let data_key = row.to_data_key();
             st_constraints.rows.insert(RowId(data_key), row);
             // Increment row count for st_constraints
-            DB_METRICS
+            METRICS
                 .rdb_num_table_rows
                 .with_label_values(&database_address, &ST_CONSTRAINTS_ID.into())
                 .inc();
@@ -340,7 +340,7 @@ impl CommittedState {
             let data_key = row.to_data_key();
             st_indexes.rows.insert(RowId(data_key), row);
             // Increment row count for st_indexes
-            DB_METRICS
+            METRICS
                 .rdb_num_table_rows
                 .with_label_values(&database_address, &ST_INDEXES_ID.into())
                 .inc();
@@ -375,7 +375,7 @@ impl CommittedState {
             let data_key = row.to_data_key();
             st_sequences.rows.insert(RowId(data_key), row);
             // Increment row count for st_sequences
-            DB_METRICS
+            METRICS
                 .rdb_num_table_rows
                 .with_label_values(&database_address, &ST_SEQUENCES_ID.into())
                 .inc();
@@ -1885,7 +1885,7 @@ impl Locking {
                     committed_state
                         .table_rows(table_id, schema)
                         .remove(&RowId(write.data_key));
-                    DB_METRICS
+                    METRICS
                         .rdb_num_table_rows
                         .with_label_values(&self.database_address, &table_id.into())
                         .dec();
@@ -1914,7 +1914,7 @@ impl Locking {
                     committed_state
                         .table_rows(table_id, schema)
                         .insert(RowId(write.data_key), product_value);
-                    DB_METRICS
+                    METRICS
                         .rdb_num_table_rows
                         .with_label_values(&self.database_address, &table_id.into())
                         .inc();

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

@@ -55,11 +55,6 @@ metrics_group!(
         #[labels(table_id: u32)]
         pub rdb_delete_by_rel_time: HistogramVec,
 
-        #[name = spacetime_num_table_rows]
-        #[help = "The number of rows in a table"]
-        #[labels(db: Address, table_id: u32)]
-        pub rdb_num_table_rows: IntGaugeVec,
-
         #[name = spacetime_num_rows_inserted_cumulative]
         #[help = "The cumulative number of rows inserted into a table"]
         #[labels(txn_type: WorkloadType, db: Address, reducer_or_query: str, table_id: u32)]

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

@@ -1,5 +1,6 @@
 use fs2::FileExt;
 use nonempty::NonEmpty;
+use spacetimedb_lib::metrics::METRICS;
 use std::borrow::Cow;
 use std::fs::{create_dir_all, File};
 use std::ops::RangeBounds;
@@ -376,7 +377,7 @@ impl RelationalDB {
             .with_label_values(&table_id.0)
             .start_timer();
         self.inner.drop_table_mut_tx(tx, table_id).map(|_| {
-            DB_METRICS
+            METRICS
                 .rdb_num_table_rows
                 .with_label_values(&self.address, &table_id.into())
                 .set(0)

crates/core/src/db/relational_db.rs

@@ -34,6 +34,8 @@ derive_more.workspace = true
 enum-as-inner.workspace = true
 hex.workspace = true
 itertools.workspace = true
+once_cell.workspace = true
+prometheus.workspace = true
 serde = { workspace = true, optional = true }
 serde_with = {workspace = true, optional = true }
 thiserror.workspace = true

crates/lib/Cargo.toml

@@ -5,6 +5,7 @@ use spacetimedb_sats::{impl_serialize, WithTypespace};
 pub mod address;
 pub mod filter;
 pub mod identity;
+pub mod metrics;
 pub mod name;
 pub mod operator;
 pub mod primary_key;

crates/lib/src/lib.rs

@@ -0,0 +1,16 @@
+use once_cell::sync::Lazy;
+use prometheus::IntGaugeVec;
+use spacetimedb_lib::Address;
+use spacetimedb_metrics::metrics_group;
+
+metrics_group!(
+    #[non_exhaustive]
+    pub struct Metrics {
+        #[name = spacetime_num_table_rows]
+        #[help = "The number of rows in a table"]
+        #[labels(db: Address, table_id: u32)]
+        pub rdb_num_table_rows: IntGaugeVec,
+    }
+);
+
+pub static METRICS: Lazy<Metrics> = Lazy::new(Metrics::new);