rust: Reduce size of some huge common objects: Plan, PlanNode, Expr<Raw>#35292
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def- wants to merge 3 commits intoMaterializeInc:mainfrom
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rust: Reduce size of some huge common objects: Plan, PlanNode, Expr<Raw>#35292def- wants to merge 3 commits intoMaterializeInc:mainfrom
def- wants to merge 3 commits intoMaterializeInc:mainfrom
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Box `Statement<Raw>` in DeclarePlan/PreparePlan (eliminating the ~832-byte AST inline), then box 17 Plan variants larger than 200 bytes. SelectPlan (184 bytes) is kept unboxed as the hot-path variant for every SELECT query. The Plan enum represents every SQL statement type. Before this change, even a simple `SELECT 1` allocated ~1888 bytes on the stack for the Plan. After: 184 bytes — a 90% reduction. DDL/EXPLAIN/SUBSCRIBE operations pay one extra heap allocation, negligible compared to their inherent catalog transaction cost. Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
Box 9 large inline fields in PlanNode<T> (GetPlan, JoinPlan, KeyValPlan, ReducePlan, TopKPlan, and MapFilterProject in 4 positions). These are constructed once during plan lowering and read during dataflow rendering, so the extra indirection is negligible. PlanNode is the LIR stored per-dataflow on every compute worker, persisting in memory for the lifetime of each dataflow. The 73% size reduction (384→104 bytes) reduces per-node memory across all active dataflows. Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
…riants
Two complementary optimizations that shrink the core AST Expr enum:
1. Expr::Function(Function<T>) → Function(Box<Function<T>>).
Function<Raw> is 240 bytes and was the single largest variant,
inflating the entire enum. Boxing reduces it to 8 bytes inline.
2. Expr::Cast { data_type: T::DataType } → { data_type: Box<T::DataType> }.
RawDataType can be up to ~48 bytes; boxing reduces to 8 bytes.
Expr<Raw> is the most numerous AST node type — every expression in
every SQL query is represented as one. The savings compound because
Expr is stored recursively: every Vec<Expr<T>> element and every
Box<Expr<T>> allocation saves 168 bytes.
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
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Extracted and cleaned up from #35255