PHP 5.4.0 Win32

Writes per second - записей в сек.
Run time - скорость выполнения участка кода связанного с буферной записью/чтением.
Max run - запоминает самую большую задержку, которая произошла.

То, что указанно в мегабайтах, это значение переданной информации за 1 сек.

Пищущий libevent 2.0.17:

Writes per second: 10523 Run time: 0.007 ms Max run: 0.036 ms
Writes per second: 10645 Run time: 0.005 ms Max run: 0.036 ms
Writes per second: 10698 Run time: 0.005 ms Max run: 0.036 ms
Writes per second: 10785 Run time: 0.006 ms Max run: 0.036 ms
Writes per second: 10998 Run time: 0.005 ms Max run: 0.043 ms
Writes per second: 11002 Run time: 0.006 ms Max run: 0.043 ms
Writes per second: 10695 Run time: 0.005 ms Max run: 0.078 ms
Writes per second: 10705 Run time: 0.005 ms Max run: 0.078 ms
Writes per second: 10702 Run time: 0.006 ms Max run: 0.094 ms
Writes per second: 10697 Run time: 0.005 ms Max run: 0.094 ms
Writes per second: 11075 Run time: 0.007 ms Max run: 0.094 ms
Writes per second: 12696 Run time: 0.007 ms Max run: 0.094 ms
Writes per second: 12680 Run time: 0.007 ms Max run: 0.124 ms
Writes per second: 11223 Run time: 0.005 ms Max run: 0.124 ms
Writes per second: 11925 Run time: 0.005 ms Max run: 0.124 ms
Writes per second: 11069 Run time: 0.005 ms Max run: 0.124 ms
Writes per second: 12392 Run time: 0.005 ms Max run: 0.124 ms
Writes per second: 10707 Run time: 0.006 ms Max run: 0.124 ms
Writes per second: 12497 Run time: 0.006 ms Max run: 0.124 ms
Writes per second: 11394 Run time: 0.005 ms Max run: 0.124 ms
Writes per second: 11572 Run time: 0.007 ms Max run: 0.124 ms
Writes per second: 12014 Run time: 0.006 ms Max run: 0.124 ms
Writes per second: 12805 Run time: 0.006 ms Max run: 0.124 ms
Writes per second: 11726 Run time: 0.006 ms Max run: 0.124 ms
Writes per second: 11127 Run time: 0.005 ms Max run: 0.158 ms
Writes per second: 12399 Run time: 0.005 ms Max run: 0.158 ms
Writes per second: 11630 Run time: 0.005 ms Max run: 0.158 ms
Writes per second: 10951 Run time: 0.006 ms Max run: 0.158 ms
Writes per second: 11609 Run time: 0.007 ms Max run: 0.158 ms
Writes per second: 11454 Run time: 0.006 ms Max run: 0.158 ms

Слушающий libevent 2.0.17:

1: 48.69 mb Run time: 0.014 ms

1: 101.41 mb Run time: 0.013 ms

1: 101.72 mb Run time: 0.014 ms

1: 102.83 mb Run time: 0.012 ms

1: 104.87 mb Run time: 0.012 ms

1: 102.22 mb Run time: 0.015 ms

1: 104.87 mb Run time: 0.013 ms

1: 101.96 mb Run time: 0.012 ms

1: 102.13 mb Run time: 0.013 ms

1: 102.05 mb Run time: 0.013 ms

1: 101.88 mb Run time: 0.015 ms

1: 122.75 mb Run time: 0.009 ms

1: 108.81 mb Run time: 0.013 ms

1: 119.65 mb Run time: 0.013 ms

1: 108.01 mb Run time: 0.014 ms

1: 111.95 mb Run time: 0.012 ms

1: 118.02 mb Run time: 0.013 ms

1: 103.08 mb Run time: 0.016 ms

1: 110.41 mb Run time: 0.014 ms

1: 117.4 mb Run time: 0.013 ms

1: 108.8 mb Run time: 0.014 ms

1: 107.71 mb Run time: 0.013 ms

1: 127.04 mb Run time: 0.013 ms

1: 105.63 mb Run time: 0.044 ms

1: 115.92 mb Run time: 0.014 ms

1: 104.07 mb Run time: 0.014 ms

1: 120.33 mb Run time: 0.012 ms

1: 109.14 mb Run time: 0.015 ms

1: 105.59 mb Run time: 0.017 ms

1: 118.11 mb Run time: 0.008 ms

Пищущий libevent 1.4.14b:

Writes per second: 16790 Run time: 0.006 ms Max run: 0.056 ms
Writes per second: 17361 Run time: 0.02 ms Max run: 0.07 ms
Writes per second: 17374 Run time: 0.007 ms Max run: 0.102 ms
Writes per second: 17387 Run time: 0.006 ms Max run: 0.102 ms
Writes per second: 17393 Run time: 0.006 ms Max run: 0.102 ms
Writes per second: 17380 Run time: 0.007 ms Max run: 0.102 ms
Writes per second: 16862 Run time: 0.009 ms Max run: 0.104 ms
Writes per second: 17316 Run time: 0.006 ms Max run: 0.104 ms
Writes per second: 17338 Run time: 0.006 ms Max run: 0.104 ms
Writes per second: 17337 Run time: 0.007 ms Max run: 0.104 ms
Writes per second: 17360 Run time: 0.006 ms Max run: 0.104 ms
Writes per second: 17304 Run time: 0.007 ms Max run: 0.104 ms
Writes per second: 17267 Run time: 0.006 ms Max run: 0.104 ms
Writes per second: 17326 Run time: 0.006 ms Max run: 0.104 ms

Слушающий libevent 1.4.14b:

1: 1.39 mb Run time: 0.014 ms

1: 162.02 mb Run time: 0.012 ms

1: 165.55 mb Run time: 0.008 ms

1: 165.71 mb Run time: 0.008 ms

1: 165.81 mb Run time: 0.013 ms

1: 165.86 mb Run time: 0.012 ms

1: 165.7 mb Run time: 0.013 ms

1: 160.83 mb Run time: 0.012 ms

1: 165.17 mb Run time: 0.008 ms

1: 165.35 mb Run time: 0.01 ms

1: 165.34 mb Run time: 0.007 ms

1: 165.56 mb Run time: 0.012 ms

1: 165.03 mb Run time: 0.007 ms

1: 164.66 mb Run time: 0.012 ms

1: 165.08 mb Run time: 0.009 ms

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Но если изменить значения в event_buffer_watermark_set
То скорость выравнивается.

Изначальные значения:

event_buffer_watermark_set($buffer, EV_WRITE, 5000, 30000);
event_buffer_watermark_set($buffer, EV_READ, 5000, 30000);