[Internal] LINQ: Fixes unbounded JIT/IL growth in SubtreeEvaluator by using interpreted expression compilation #5488
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Fix the evaluation of constant expressions by using preferInterpretation: true. Because Expression.Compile() emits a new DynamicMethod each time, workloads that frequently build distinct expression trees experience unbounded JIT/IL growth and increasing memory usage in the process’ native RSS (anon_rx).
Ofekw
requested review from
adityasa,
khdang,
kirankumarkolli and
sboshra
as code owners
Ofekw
changed the title
Diego-Perez-Botero
approved these changes
Nov 13, 2025
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Description
This change fixes a JIT/IL memory growth issue caused by the Cosmos LINQ provider’s
SubtreeEvaluator.EvaluateConstantmethod.The previous implementation called
Expression.Compile()each time an expression tree was evaluated, which emitted a new DynamicMethod and led to unbounded JIT code generation in long-running services.The fix replaces:
with
to use the interpreted execution mode instead of generating new dynamic IL.
This change eliminates the unmanaged memory and JIT growth while preserving functional behavior.
No public APIs are changed, and no behavioral differences are expected aside from improved stability in memory-sensitive workloads.
Type of change
Closing issues
Closes #5487 (JIT/IL growth due to
SubtreeEvaluator.EvaluateConstantcallingExpression.Compile()repeatedly)