The tests were run over several days under both Windows XP (SP3) and Vista x86 (SP1).
What exo.performance.network discovered was "another example of unchecked Microsoft code 'bloat,' complete with 'shirt-bursting, waistline-stretching' memory consumption and the kind of CPU-hogging thread growth normally reserved for massively parallel server farms."
In a multi-tab browsing session against 10 websites under Vista, IE8 grabbed about 380MB of memory, in contrast with 250MB consumed by IE7 and just 159MB by Firefox 3.0.1.
That makes IE8 nearly one and-a-half times more memory intensive than IE7 and well more than twice as greedy as Firefox.
With regard to the number of threads spawned by the browsers, IE8 created approaching three times the workload of IE7 and more than five times that of Firefox.
IE8 spawned a staggering 171 concurrent threads, while IE7 spawned a somewhat less resource-hogging 65 threads and Firefox somehow managed to make do with spawning merely 29 threads.
Nonetheless, Firefox displayed websites faster than both IE7 and IE8, according to the test report, although it didn't present any timing figures. The test report conjectured that Firefox uses "a more efficient rendering engine employing fewer threads in exchange for faster linear performance."
And it appears that IE8 has such an overly complex design that it has trouble getting out of its own way to actually use the CPU resources available, though running under Vista imposed significant CPU overhead too.
IE8 used average CPU time of 22 per cent when running under Windows XP and 33 per cent under Vista.
IE7 used 13 per cent CPU under Windows XP and 24 per cent under Vista.
Firefox made the best use of the available CPU resources, consuming 33 per cent CPU under Windows XP and 48 per cent under Vista.
The report observes that, "By delivering superior performance while maintaining a nearly [two times] smaller memory and CPU [threads] footprint across the board, Firefox 3.01 proves once again that the open source community can often trump even the most well-funded commercial projects when it comes to delivering efficient, streamlined code."
The test report speculated that Microsoft hopes that IE8 will drive customers into further hardware replacements to acquire systems with more than 4GB of memory running 64-bit flavours of Windows.
It also observed that, with its proliferation of threads and multiple execution processes – six discrete instances of iexplore.exe in the tests – IE8 is being positioned by Microsoft to take advantage of more CPU cores in future Intel and AMD chip designs.
But it added that this positioning comes "at the cost of overwhelming today's single and dual-core PCs."
IE8 is a resource hog
By Egan Orion on Sep 3, 2008 11:23PM