address feedback (other than LirMapping fix)

doc/user/content/sql/system-catalog/mz_introspection.md

@@ -222,6 +222,19 @@ The `mz_dataflow_channel_operators` view associates [dataflow] channels with the
 
 <!-- RELATION_SPEC_UNDOCUMENTED mz_introspection.mz_dataflow_channel_operators_per_worker -->
 
+## `mz_dataflow_global_ids`
+
+The `mz_dataflow_global_ids` view associates [dataflow] ids with global ids (ids of the form `u8` or `t5`).
+
+<!-- RELATION_SPEC mz_introspection.mz_dataflow_global_ids -->
+
+| Field        | Type      | Meaning                                    |
+|------------- | -------   | --------                                   |
+| `id`         | [`uint8`] | The dataflow ID.                           |
+| `global_id`  | [`text`]  | A global ID associated with that dataflow. |
+
+<!-- RELATION_SPEC_UNDOCUMENTED mz_introspection.mz_compute_dataflow_global_ids_per_worker -->
+
 ## `mz_dataflow_operators`
 
 The `mz_dataflow_operators` view describes the [dataflow] operators in the system.
@@ -292,6 +305,29 @@ through a hierarchical scheme for either aggregation or Top K computations.
 | `savings`       | [`numeric`]          | A conservative estimate of the amount of memory in bytes to be saved by applying the hint.                |
 | `hint`          | [`double precision`] | The hint value that will eliminate `to_cut` levels from the region's hierarchy.                           |
 
+## `mz_lir_mapping`
+
+The `mz_lir_mapping` view describes the low-level internal representation (LIR) plan that corresponds to global ids.
+LIR is a higher-level representation than dataflows; this view is used for profiling and debugging indices and materialized views.
+Note that LIR is not a stable interface and may change at any time.
+In particular, you should not attempt to parse `operator` descriptions.
+LIR nodes are implemented by zero or more dataflow operators with sequential ids.
+We use the range `[operator_id_start, operator_id_end)` to record this information.
+If an LIR node was implemented without any dataflow operators, `operator_id_start` will be equal to `operator_id_end`.
+
+<!-- RELATION_SPEC mz_introspection.mz_lir_mapping -->
+| Field             | Type      | Meaning
+| ---------         | --------  | -----------
+| global_id         | [`text`]  | The global ID.
+| lir_id            | [`uint8`] | The LIR node ID.
+| operator          | [`text`]  | The LIR operator, in the format `OperatorName INPUTS [OPTIONS]`.
+| parent_lir_id     | [`uint8`] | The parent of this LIR node. May be `NULL`.
+| nesting           | [`uint2`] | The nesting level of this LIR node.
+| operator_id_start | [`uint8`] | The first dataflow operator ID implementing this LIR operator (inclusive).
+| operator_id_end   | [`uint8`] | The first dataflow operator ID _after_ this LIR operator (exclusive).
+
+<!-- RELATION_SPEC_UNDOCUMENTED mz_introspection.mz_compute_lir_mapping_per_worker -->
+
 ## `mz_message_counts`
 
 The `mz_message_counts` view describes the messages and message batches sent and received over the [dataflow] channels in the system.
@@ -395,6 +431,7 @@ The `mz_scheduling_parks_histogram` view describes a histogram of [dataflow] wor
 [`numeric`]: /sql/types/numeric
 [`text`]: /sql/types/text
 [`uuid`]: /sql/types/uuid
+[`uint2`]: /sql/types/uint2
 [`uint8`]: /sql/types/uint8
 [`uint8 list`]: /sql/types/list
 [arrangement]: /get-started/arrangements/#arrangements
@@ -408,7 +445,3 @@ The `mz_scheduling_parks_histogram` view describes a histogram of [dataflow] wor
 <!-- RELATION_SPEC_UNDOCUMENTED mz_introspection.mz_dataflow_operator_reachability -->
 <!-- RELATION_SPEC_UNDOCUMENTED mz_introspection.mz_dataflow_operator_reachability_per_worker -->
 <!-- RELATION_SPEC_UNDOCUMENTED mz_introspection.mz_dataflow_operator_reachability_raw -->
-<!-- RELATION_SPEC_UNDOCUMENTED mz_introspection.mz_compute_lir_mapping_per_worker -->
-<!-- RELATION_SPEC_UNDOCUMENTED mz_introspection.mz_compute_dataflow_globalids_per_worker -->
-<!-- RELATION_SPEC_UNDOCUMENTED mz_introspection.mz_lir_mapping -->
-<!-- RELATION_SPEC_UNDOCUMENTED mz_introspection.mz_dataflow_globalids -->

src/catalog/src/builtin.rs

@@ -1911,11 +1911,11 @@ pub static MZ_COMPUTE_EXPORTS_PER_WORKER: LazyLock<BuiltinLog> = LazyLock::new(|
     access: vec![PUBLIC_SELECT],
 });
 
-pub static MZ_COMPUTE_DATAFLOW_GLOBALIDS_PER_WORKER: LazyLock<BuiltinLog> =
+pub static MZ_COMPUTE_DATAFLOW_GLOBAL_IDS_PER_WORKER: LazyLock<BuiltinLog> =
     LazyLock::new(|| BuiltinLog {
-        name: "mz_compute_dataflow_globalids_per_worker",
+        name: "mz_compute_dataflow_global_ids_per_worker",
         schema: MZ_INTROSPECTION_SCHEMA,
-        oid: oid::LOG_MZ_COMPUTE_DATAFLOW_GLOBALIDS_PER_WORKER_OID,
+        oid: oid::LOG_MZ_COMPUTE_DATAFLOW_GLOBAL_IDS_PER_WORKER_OID,
         variant: LogVariant::Compute(ComputeLog::DataflowGlobal),
         access: vec![PUBLIC_SELECT],
     });
@@ -4072,13 +4072,13 @@ WHERE worker_id = 0",
 });
 
 pub static MZ_DATAFLOW_GLOBAL_IDS: LazyLock<BuiltinView> = LazyLock::new(|| BuiltinView {
-    name: "mz_dataflow_globalids",
+    name: "mz_dataflow_global_ids",
     schema: MZ_INTROSPECTION_SCHEMA,
-    oid: oid::VIEW_MZ_DATAFLOW_GLOBALIDS_OID,
+    oid: oid::VIEW_MZ_DATAFLOW_GLOBAL_IDS_OID,
     column_defs: None,
     sql: "
 SELECT id, global_id
-FROM mz_introspection.mz_compute_dataflow_globalids_per_worker
+FROM mz_introspection.mz_compute_dataflow_global_ids_per_worker
 WHERE worker_id = 0",
     access: vec![PUBLIC_SELECT],
 });
@@ -9136,7 +9136,7 @@ pub static BUILTINS_STATIC: LazyLock<Vec<Builtin<NameReference>>> = LazyLock::ne
         Builtin::Log(&MZ_DATAFLOW_ADDRESSES_PER_WORKER),
         Builtin::Log(&MZ_DATAFLOW_OPERATOR_REACHABILITY_RAW),
         Builtin::Log(&MZ_COMPUTE_EXPORTS_PER_WORKER),
-        Builtin::Log(&MZ_COMPUTE_DATAFLOW_GLOBALIDS_PER_WORKER),
+        Builtin::Log(&MZ_COMPUTE_DATAFLOW_GLOBAL_IDS_PER_WORKER),
         Builtin::Log(&MZ_MESSAGE_COUNTS_RECEIVED_RAW),
         Builtin::Log(&MZ_MESSAGE_COUNTS_SENT_RAW),
         Builtin::Log(&MZ_MESSAGE_BATCH_COUNTS_RECEIVED_RAW),

src/compute-client/src/logging.rs

@@ -543,14 +543,14 @@ impl LogVariant {
                 .with_column("nesting", ScalarType::UInt16.nullable(false))
                 .with_column("operator_id_start", ScalarType::UInt64.nullable(true))
                 .with_column("operator_id_end", ScalarType::UInt64.nullable(true))
-                .with_key(vec![0, 1])
+                .with_key(vec![0, 1, 2])
                 .finish(),
 
             LogVariant::Compute(ComputeLog::DataflowGlobal) => RelationDesc::builder()
                 .with_column("id", ScalarType::UInt64.nullable(false))
                 .with_column("worker_id", ScalarType::UInt64.nullable(false))
                 .with_column("global_id", ScalarType::String.nullable(false))
-                .with_key(vec![0])
+                .with_key(vec![0, 1])
                 .finish(),
         }
     }

src/compute-types/src/plan.rs

@@ -188,6 +188,8 @@ impl AvailableCollections {
 }
 
 /// An identifier for an LIR node.
+///
+/// LirIds start at 1, not 0, which let's us get a better struct packing in `ComputeEvent::LirMapping`.
 #[derive(Clone, Copy, Debug, Deserialize, Eq, Ord, PartialEq, PartialOrd, Serialize)]
 pub struct LirId(NonZeroU64);
 
@@ -1147,6 +1149,16 @@ mod tests {
 
     use super::*;
 
+    #[mz_ore::test]
+    fn test_option_lirid_fits_in_usize() {
+        let option_lirid_size = std::mem::size_of::<Option<LirId>>();
+        let usize_size = std::mem::size_of::<usize>();
+        assert!(
+            option_lirid_size <= usize_size,
+            "Option<LirId> (size {option_lirid_size}) should fit in usize (size {usize_size})"
+        );
+    }
+
     proptest! {
         #![proptest_config(ProptestConfig::with_cases(10))]
         #[mz_ore::test]