fix: only show fifo warnings when perf env is present

[not-matthias]

No description provided.

[codspeed-hq]

CodSpeed Instrumentation Performance Report

Merging #112 will degrade performances by 6.78%

_{Comparing cod-1081-codspeed-rust-shows-warning-in-walltime-when-not-running (cc79130) with main (d712959)}

Summary

⚡ 10 improvements
❌ 1 regressions
✅ 156 untouched benchmarks

⚠️ Please fix the performance issues or acknowledge them on CodSpeed.

Benchmarks breakdown

	Benchmark	BASE	HEAD	Change
⚡	bench_array1[10]	225 ns	195.8 ns	+14.89%
⚡	bench_array2[10]	225 ns	195.8 ns	+14.89%
⚡	mut_borrow	924.2 ns	895 ns	+3.26%
⚡	recursive[0]	240.3 ns	211.1 ns	+13.82%
⚡	recursive[5]	320.3 ns	291.1 ns	+10.02%
❌	recursive_memoized[BTreeMap<u64, u64>, 0]	400.8 ns	430 ns	-6.78%
⚡	sleep_100ns	566.1 ns	536.9 ns	+5.43%
⚡	sleep_100us	566.1 ns	536.9 ns	+5.43%
⚡	sleep_1ms	566.1 ns	536.9 ns	+5.43%
⚡	sleep_1ns	566.1 ns	536.9 ns	+5.43%
⚡	sleep_1us	566.1 ns	536.9 ns	+5.43%

[codspeed-hq]

CodSpeed WallTime Performance Report

Merging #112 will degrade performances by 19.74%

_{Comparing cod-1081-codspeed-rust-shows-warning-in-walltime-when-not-running (cc79130) with main (d712959)}

Summary

⚡ 19 improvements
❌ 8 regressions
✅ 127 untouched benchmarks

⚠️ Please fix the performance issues or acknowledge them on CodSpeed.

Benchmarks breakdown

	Benchmark	BASE	HEAD	Change
❌	fibonacci_custom_measurement	380 ns	408 ns	-6.86%
❌	large_drop	165 µs	179.2 µs	-7.93%
❌	iter_with_setup	36 ns	39 ns	-7.69%
⚡	from_elem[16384]	859 ns	824 ns	+4.25%
❌	from_elem[2048]	243 ns	257 ns	-5.45%
❌	from_elem[4096]	320 ns	334 ns	-4.19%
⚡	from_elem[8192]	507 ns	487 ns	+4.11%
❌	from_elem_decimal[2048]	243 ns	257 ns	-5.45%
⚡	print_env_hello	2.2 µs	1.9 µs	+16.14%
⚡	graph_coloring[5]	992 ns	947 ns	+4.75%
⚡	hamiltonian_cycle[5]	654 ns	629 ns	+3.97%
⚡	hamiltonian_cycle[7]	816 ns	791 ns	+3.16%
⚡	permutations[3]	812 ns	692 ns	+17.34%
⚡	permutations[4]	2.7 µs	2.3 µs	+16.59%
⚡	permutations[5]	14.7 µs	11 µs	+33.74%
❌	permutations[6]	66.8 µs	73.2 µs	-8.66%
⚡	permutations[7]	839.9 µs	790.2 µs	+6.29%
⚡	count_set_bits[0]	8 ns	7 ns	+14.29%
⚡	count_set_bits[1024]	8 ns	7 ns	+14.29%
⚡	count_set_bits[255]	8 ns	7 ns	+14.29%
...	...	...	...	...

ℹ️ Only the first 20 benchmarks are displayed. Go to the app to view all benchmarks.

[art049]

looks good