It’s perfectly normal to see two or more iexplore.exe processes in the Task Manager when an Internet Explorer 8 window is open. This is due to a change implemented in Internet Explorer 8 where the frame and tabs are split, each having their own processes. Each tab has its own* process so that the rest of the tabs and the browser frame/window are not affected when a single tab process crashes.
Note: If you have 60 tabs open you won’t see 60 iexplore.exe processes. There may 20 iexplore.exe processes, with each process hosting a number of tabs. As per the IE Team Blog, this a balancing act between performance and reliablility. Quoting from Internet Explorer Team Blog:
The more capable your system is, the more processes we create, up to a point. It’s based on a curve. If you use 60 tabs at a time, we don’t want to create 60 tab processes, as the perf impact would be too severe. It’s a balancing act between performance and relability. For example, if you had 60 tabs open and we created 20 processes, we would co-locate 3 tabs in each process (60 tabs / 20 processes). If a single tab process failed, we would only have to recover 2 other tabs. The benefit of "perfect" isolation would not be worth the cost of 40 extra processes in most cases. It’s a case of diminishing returns.
Apart from this, there are other architectural changes made in Internet Explorer 8, which is collectively known as Loosely-Coupled IE (LCIE). For detailed information on these changes, see the following posts at the IE Team Blog.
IEBlog : IE8 and Reliability
IEBlog : Trustworthy Browsing with IE8
The more capable your system is, the more processes we create, up to a point. It’s based on a curve. If you use 60 tabs at a time, we don’t want to create 60 tab processes, as the perf impact would be too severe. It’s a balancing act between performance and relability. For example, if you had 60 tabs open and we created 20 processes, we would co-locate 3 tabs in each process (60 tabs / 20 processes). If a single tab process failed, we would only have to recover 2 other tabs. The benefit of "perfect" isolation would not be worth the cost of 40 extra processes in most cases. It’s a case of diminishing returns.
Apart from this, there are other architectural changes made in Internet Explorer 8, which is collectively known as Loosely-Coupled IE (LCIE). For detailed information on these changes, see the following posts at the IE Team Blog.
IEBlog : IE8 and Reliability
IEBlog : Trustworthy Browsing with IE8
