Switch to pooling copy-on-write instantiation strategy for WASM (#11232)

* Switch to pooling copy-on-write instantiation strategy for WASM

* Fix benchmark compilation

* Fix `cargo fmt`

* Fix compilation of another benchmark I've missed

* Cleanups according to review comments

* Move `max_memory_size` to `Semantics`

* Set `memory_guaranteed_dense_image_size` to `max_memory_size`

* Rename `wasm_instantiation_strategy` to `wasmtime_instantiation_strategy`

* Update the doc-comments regarding the instantiation strategy

* Extend the integration tests to test every instantiation strategy

* Don't drop the temporary directory until the runtime is dropped in benchmarks

* Don't drop the temporary directory until the runtime is dropped in tests

substrate/bin/node/testing/src/bench.rs

@@ -46,7 +46,7 @@ use sc_client_api::{
 };
 use sc_client_db::PruningMode;
 use sc_consensus::{BlockImport, BlockImportParams, ForkChoiceStrategy, ImportResult, ImportedAux};
-use sc_executor::{NativeElseWasmExecutor, WasmExecutionMethod};
+use sc_executor::{NativeElseWasmExecutor, WasmExecutionMethod, WasmtimeInstantiationStrategy};
 use sp_api::ProvideRuntimeApi;
 use sp_block_builder::BlockBuilder;
 use sp_consensus::BlockOrigin;
@@ -398,7 +398,14 @@ impl BenchDb {
 		let backend = sc_service::new_db_backend(db_config).expect("Should not fail");
 		let client = sc_service::new_client(
 			backend.clone(),
-			NativeElseWasmExecutor::new(WasmExecutionMethod::Compiled, None, 8, 2),
+			NativeElseWasmExecutor::new(
+				WasmExecutionMethod::Compiled {
+					instantiation_strategy: WasmtimeInstantiationStrategy::PoolingCopyOnWrite,
+				},
+				None,
+				8,
+				2,
+			),
 			&keyring.generate_genesis(),
 			None,
 			None,