Added pg_statio_all_tables metric

Author: dementii-priadko

config/pgwatch-prometheus/metrics.yml

@@ -2068,6 +2068,34 @@ metrics:
     gauges:
       - config_value_normalized
 
+  pg_statio_all_tables:
+    description: >
+      Retrieves table-level I/O statistics from the PostgreSQL `pg_statio_all_tables` view, providing insights into I/O operations for all tables.
+      It returns block-level read and hit statistics for heap, index, TOAST, and TOAST index operations broken down by schema and table.
+      This metric helps administrators monitor table-level I/O performance and identify which tables are generating the most I/O activity.
+      Compatible with all PostgreSQL versions.
+    sqls:
+      11: |-
+        select /* pgwatch_generated */
+          (extract(epoch from now()) * 1e9)::int8 as epoch_ns,
+          current_database() as tag_datname,
+          schemaname as tag_schemaname,
+          relname as tag_relname,
+          heap_blks_read,
+          heap_blks_hit,
+          idx_blks_read,
+          idx_blks_hit,
+          toast_blks_read,
+          toast_blks_hit,
+          tidx_blks_read,
+          tidx_blks_hit
+        from
+          pg_statio_all_tables
+        where
+          heap_blks_read > 0 or idx_blks_read > 0 or toast_blks_read > 0 or tidx_blks_read > 0
+    gauges:
+      - '*'
+
 
 presets:
   full:
@@ -2092,6 +2120,7 @@ presets:
       pg_stat_user_indexes: 30
       pg_stat_statements: 30
       pg_stat_replication: 30
+      pg_statio_all_tables: 30
       pg_total_relation_size: 30
       pg_blocked: 30
       pg_long_running_transactions: 30