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webassembly_udf_* session settings

Autogenerated from ClickHouse system tables

These settings are available in system.settings and are autogenerated from the ClickHouse snapshot.

webassembly_udf_max_fuel

Fuel limit per WebAssembly UDF instance execution. Each WebAssembly instruction consumes some amount of fuel. The value is scaled by 1024 before being passed to the runtime, so webassembly_udf_max_fuel = 1 corresponds to approximately 1024 fuel units. Set to 0 for no finite limit. Applies only to functions whose per-function setting webassembly_udf_enable_fuel is true, which is the default.

webassembly_udf_max_input_block_size

Maximum number of rows passed to a WebAssembly UDF in a single call. A non-zero value caps the rows per call and applies to every ABI.

Set to 0 to size the calls by their serialized input instead. That applies to ABI BUFFERED_V1 alone, the only ABI that serializes a whole input block into guest memory: its blocks are split so that a call’s input stays within webassembly_udf_input_split_memory_ratio of the module’s linear memory. ROW_DIRECT passes its arguments as WebAssembly values and ASSEMBLYSCRIPT builds one object per row, so neither has a serialized input to size a call by, and 0 leaves their pipeline block whole.

webassembly_udf_max_instances

Maximum number of WebAssembly UDF instances that can run in parallel per function.

webassembly_udf_max_memory

Memory limit in bytes per WebAssembly UDF instance.