# 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::Extension; #[op] fn op_nop() -> usize { 9 } fn setup() -> Vec { vec![Extension { name: "my_ext" ops: std::borrow::Cow::Borrowed(&[op_nop::DECL]) }] } 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); ```