December 2, 2011

Why Is Safari 5.1.2 So Slow?

Why is Safari 5.1.2 so slow? Specifically Safari 5.1.2 on PC.
Safari 5.1.2 is sluggish. With Safari, web pages take a long time to load. It creates a very bad user experience. All pages are slow
  • Text-only pages
  • Text, images, video pages
  • Pages with or without flash
You get used to seeing Safari’s spinning wheel.

Safari’s “slowness” has been there at least since July 2011 (Safari 5.1) if not longer.

While Safari 5.1.2 seems to have fixed other issues such as Safari.exe fails to close and webkit2webprocess.exe, the speed issue is still open.

It has been at least 4 months, when will Apple fix Safari’s speed issues?

Here is a simple Safari vs Chrome speed test, which shows the problem.

Test Results
  1. Open 8 windows of European Universities Advertising in US  at SimpleRNA
    Chrome: 16.4 seconds
    Safari: 84 seconds

    Safari is 5x slower than Chrome.

    This page displays ads (which add some variability) and sometimes flash-ads (which Safari does not like). Therefore, here is another test without those elements.

  2. Open 8 windows of Safari 5.1.2
    Chrome: 6.5 sec
    Safari: 26 sec

    Safari is 4x slower than Chrome.
Other pages show similar results. Chrome is always much faster than Safari.

Test Setup
  1. The network connection used Google DNS servers
    Primary DNS server –
    Alternate DNS server –

    Using Open DNS -, - or ISP’s DNS shows similar results.

  2. Cache, cookies etc were all cleared before the start of the test

  3. A stopwatch was started/stopped manually to measure the page load time.