Measure time after serialization.

[TimonPost]

Description of Changes

Take time after serializing data to stream to be more accurate.

Api of begin_scope is a bit weird now for tests. Could potentially split up in different functions that are used by test/normal code.

[emilk]

Please run cargo bench and see that this doesn't slow down the profiler!

[TimonPost]

macbook with M1

test result: ok. 0 passed; 0 failed; 6 ignored; 0 measured; 0 filtered out; finished in 0.00s

     Running benches/benchmark.rs (target/release/deps/benchmark-9041bbb2765f19e3)
profile_function        time:   [58.279 ns 58.388 ns 58.540 ns]
                        change: [-8.9887% -5.9113% -3.7870%] (p = 0.00 < 0.05)
                        Performance has improved.
Found 14 outliers among 100 measurements (14.00%)
  7 (7.00%) high mild
  7 (7.00%) high severe

profile_function_data   time:   [58.990 ns 59.076 ns 59.194 ns]
                        change: [-1.9866% -1.4209% -0.8548%] (p = 0.00 < 0.05)
                        Change within noise threshold.
Found 13 outliers among 100 measurements (13.00%)
  3 (3.00%) high mild
  10 (10.00%) high severe

profile_scope           time:   [58.219 ns 58.441 ns 58.723 ns]
                        change: [-4.6145% -4.1899% -3.7831%] (p = 0.00 < 0.05)
                        Performance has improved.
Found 13 outliers among 100 measurements (13.00%)
  3 (3.00%) low mild
  2 (2.00%) high mild
  8 (8.00%) high severe

profile_scope_data      time:   [58.851 ns 58.939 ns 59.049 ns]
                        change: [-0.9931% -0.6718% -0.3677%] (p = 0.00 < 0.05)
                        Change within noise threshold.
Found 12 outliers among 100 measurements (12.00%)
  1 (1.00%) low mild
  3 (3.00%) high mild
  8 (8.00%) high severe

profile_function_off    time:   [936.78 ps 937.74 ps 938.84 ps]
                        change: [-3.2609% -2.9127% -2.5542%] (p = 0.00 < 0.05)
                        Performance has improved.
Found 11 outliers among 100 measurements (11.00%)
  5 (5.00%) high mild
  6 (6.00%) high severe

profile_function_data_off
                        time:   [937.98 ps 939.71 ps 941.84 ps]
                        change: [-3.2669% -2.8004% -2.3128%] (p = 0.00 < 0.05)
                        Performance has improved.
Found 12 outliers among 100 measurements (12.00%)
  3 (3.00%) high mild
  9 (9.00%) high severe

profile_scope_off       time:   [937.85 ps 939.11 ps 940.55 ps]
                        change: [-4.7535% -4.3033% -3.8568%] (p = 0.00 < 0.05)
                        Performance has improved.
Found 10 outliers among 100 measurements (10.00%)
  5 (5.00%) high mild
  5 (5.00%) high severe

profile_scope_data_off  time:   [945.14 ps 948.97 ps 952.68 ps]
                        change: [-2.4174% -2.1027% -1.8036%] (p = 0.00 < 0.05)
                        Performance has improved.
Found 7 outliers among 100 measurements (7.00%)
  6 (6.00%) high mild
  1 (1.00%) high severe

Will re-run on my windows PC, there I did not directly detect much changes.