Internet Explorer 8 – users complained it was freezing

They were just upgraded from Internet Explorer 6.  I have two guesses why this was happening:

  1. IE6 would have been freezing as well, but because website was in it’s own browser process, the user would just close the frozen Internet Explorer, and that was that.
  2. users now had TABBED browsing, and were using the new functionally to open websites in TABs.  A website would freeze, say due to Adobe Flash or Shockwave; and Internet Explorer 8 would freeze.

The solution I eventually found?

For up to 10 TABs, allow each TAB to run it’s own iexplore.exe process.  You can do this via a registry key called TabProcGrowth.

TabProcGrowth >1: multiple tab processes will be used to execute the tabs at a given MIC level for a single frame process. In general, new processes are created until the TabProcGrowth number is met, and then tabs are load balanced across the tab processes.
Microsoft "We know IE!" Blog: Opening a New Tab …

TabProcGrowth is a DWORD registry entry, which you set under HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Internet Explorer\Main .

For my users, I’ve set TabProcGrowth to 10.

Further reading:
We know IE! blog: Opening a New Tab may launch a New Process with Internet Explorer 8.0
HttpWatch: Seven Things You Should Known About IE 8