Решил провести тестирование скорости работы JavaScript трех версий популярного браузера:

  • Firefox 3.6.8
  • Firefox 4.0 beta 2
  • Minefield 4.0 beta 4 pre (ночная сборка 2010.08.08)

Потратив некоторое время в SunSpider, я получил довольно интересные и близкие к действительности результаты:

Mozilla/5.0 (Windows; U; Windows NT 6.1; ru; rv:1.9.2.8) Gecko/20100722 Firefox/3.6.8

============================================
RESULTS (means and 95% confidence intervals)
--------------------------------------------
Total:                  729.8ms +/- 1.7%
--------------------------------------------

  3d:                   118.6ms +/- 1.2%
    cube:                29.4ms +/- 3.8%
    morph:               36.6ms +/- 1.9%
    raytrace:            52.6ms +/- 2.7%

  access:               104.0ms +/- 2.4%
    binary-trees:        27.2ms +/- 3.8%
    fannkuch:            51.4ms +/- 1.3%
    nbody:               16.8ms +/- 3.3%
    nsieve:               8.6ms +/- 12.9%

  bitops:                29.4ms +/- 5.7%
    3bit-bits-in-byte:    1.0ms +/- 0.0%
    bits-in-byte:         8.2ms +/- 16.6%
    bitwise-and:          2.0ms +/- 0.0%
    nsieve-bits:         18.2ms +/- 3.1%

  controlflow:           31.0ms +/- 0.0%
    recursive:           31.0ms +/- 0.0%

  crypto:                37.2ms +/- 2.8%
    aes:                 22.0ms +/- 5.7%
    md5:                  9.6ms +/- 7.1%
    sha1:                 5.6ms +/- 12.2%

  date:                 126.0ms +/- 2.1%
    format-tofte:        62.4ms +/- 3.3%
    format-xparb:        63.6ms +/- 1.7%

  math:                  44.8ms +/- 20.7%
    cordic:              26.6ms +/- 35.1%
    partial-sums:        13.0ms +/- 0.0%
    spectral-norm:        5.2ms +/- 20.0%

  regexp:                40.8ms +/- 1.4%
    dna:                 40.8ms +/- 1.4%

  string:               198.0ms +/- 2.5%
    base64:               8.0ms +/- 0.0%
    fasta:               44.6ms +/- 3.2%
    tagcloud:            59.2ms +/- 3.8%
    unpack-code:         64.2ms +/- 3.2%
    validate-input:      22.0ms +/- 10.6%
Mozilla/5.0 (Windows; Windows NT 6.1; WOW64; rv:2.0b2) Gecko/20100720 Firefox/4.0b2

============================================
RESULTS (means and 95% confidence intervals)
--------------------------------------------
Total:                  513.2ms +/- 0.9%
--------------------------------------------

  3d:                    77.8ms +/- 10.9%
    cube:                25.0ms +/- 0.0%
    morph:               21.0ms +/- 39.7%
    raytrace:            31.8ms +/- 1.7%

  access:                70.2ms +/- 1.9%
    binary-trees:        14.0ms +/- 0.0%
    fannkuch:            34.0ms +/- 0.0%
    nbody:               14.0ms +/- 6.3%
    nsieve:               8.2ms +/- 6.8%

  bitops:                22.4ms +/- 3.0%
    3bit-bits-in-byte:    0.4ms +/- 170.2%
    bits-in-byte:         7.0ms +/- 0.0%
    bitwise-and:          1.2ms +/- 46.3%
    nsieve-bits:         13.8ms +/- 4.0%

  controlflow:            6.2ms +/- 9.0%
    recursive:            6.2ms +/- 9.0%

  crypto:                28.8ms +/- 8.3%
    aes:                 17.6ms +/- 10.7%
    md5:                  7.2ms +/- 7.7%
    sha1:                 4.0ms +/- 0.0%

  date:                  68.8ms +/- 1.5%
    format-tofte:        43.4ms +/- 1.6%
    format-xparb:        25.4ms +/- 2.7%

  math:                  40.2ms +/- 4.0%
    cordic:              22.4ms +/- 3.0%
    partial-sums:        12.8ms +/- 4.3%
    spectral-norm:        5.0ms +/- 17.6%

  regexp:                45.0ms +/- 0.0%
    dna:                 45.0ms +/- 0.0%

  string:               153.8ms +/- 1.8%
    base64:               6.8ms +/- 8.2%
    fasta:               18.2ms +/- 3.1%
    tagcloud:            55.2ms +/- 2.9%
    unpack-code:         53.0ms +/- 1.7%
    validate-input:      20.6ms +/- 9.2%
Mozilla/5.0 (Windows NT 6.1; WOW64; rv:2.0b4pre) Gecko/20100808 Minefield/4.0b4pre

============================================
RESULTS (means and 95% confidence intervals)
--------------------------------------------
Total:                  479.2ms +/- 1.5%
--------------------------------------------

  3d:                    76.6ms +/- 10.6%
    cube:                24.0ms +/- 3.7%
    morph:               18.8ms +/- 37.8%
    raytrace:            33.8ms +/- 3.1%

  access:                65.8ms +/- 1.6%
    binary-trees:        14.2ms +/- 7.3%
    fannkuch:            36.4ms +/- 3.1%
    nbody:                6.8ms +/- 8.2%
    nsieve:               8.4ms +/- 8.1%

  bitops:                18.8ms +/- 5.5%
    3bit-bits-in-byte:    0.2ms +/- 278.0%
    bits-in-byte:         7.6ms +/- 9.0%
    bitwise-and:          1.2ms +/- 46.3%
    nsieve-bits:          9.8ms +/- 5.7%

  controlflow:            6.0ms +/- 0.0%
    recursive:            6.0ms +/- 0.0%

  crypto:                26.4ms +/- 5.4%
    aes:                 15.4ms +/- 4.4%
    md5:                  7.4ms +/- 9.2%
    sha1:                 3.6ms +/- 18.9%

  date:                  66.2ms +/- 0.8%
    format-tofte:        40.4ms +/- 1.7%
    format-xparb:        25.8ms +/- 2.2%

  math:                  43.0ms +/- 2.0%
    cordic:              24.0ms +/- 0.0%
    partial-sums:        12.4ms +/- 5.5%
    spectral-norm:        6.6ms +/- 10.3%

  regexp:                43.6ms +/- 5.2%
    dna:                 43.6ms +/- 5.2%

  string:               132.8ms +/- 1.2%
    base64:               5.2ms +/- 10.7%
    fasta:               17.2ms +/- 3.2%
    tagcloud:            51.4ms +/- 4.4%
    unpack-code:         46.2ms +/- 7.5%
    validate-input:      12.8ms +/- 4.3%

Подводя итоги, становится видна тенденция, что новый браузер Firefox 4 от организации Mozilla будет обрабатывать JavaScript примерно в 1.5-2 раза шустрее, чем нынешний. Выход браузера запланирован на конец 2010 года.