# Benching utility for `deno_core` op system Example: ```rust use deno_bench_util::bench_or_profile; use deno_bench_util::bencher::{benchmark_group, Bencher}; use deno_bench_util::bench_js_sync}; use deno_core::op_sync; use deno_core::serialize_op_result; use deno_core::Extension; use deno_core::JsRuntime; use deno_core::Op; use deno_core::OpState; fn setup() -> Vec { let custom_ext = Extension::builder() .ops(vec![ ("op_nop", |state, _| { Op::Sync(serialize_op_result(Ok(9), state)) }), ]) .build(); vec![ // deno_{ext}::init(...), custom_ext, ] } fn bench_op_nop(b: &mut Bencher) { bench_js_sync(b, r#"Deno.core.ops.op_nop();"#, setup); } benchmark_group!(benches, bench_op_nop); bench_or_profile!(benches); ```