A few points:
a) It is not only what you use, but how you use it that counts ;-) IE (which Maxthon is a shell for), is pretty conservative in memory allocation. But its navigation performance is horrid. Opera uses memory for fast history navigation more efficiently than any other browser on the planet. Using 3 tabs of google images
, I can instantly navigate through 600 images worth of data in Opera where IE fails after a few. The raw memory numbers are not too different, but functionality certainly is!
b) Using memory can result in much better performance. Though sadly not available anymore, Mark Russinovitch's great article about hoax memory optimizers was scathing on the idea of free RAM
. Modern OS's work better when memory that you paid for is actually used. Worrying about memory allocation is largely futile, as performance is much better overall. I know at least Opera has done extensive work on balancing this. If you have lots of free RAM they will use it because it results in better overall performance. Opera's core works on mobile phones, so it can render in extremely limited conditions. Every byte is tweaked and optimized. On desktop, they simply extend cacheing of data to drive up speed.
c) The OS and the machine, not only the app, is responsible for memory allocation. At least for Opera, it uses less memory when there is less available (I've done multi-tab browsing of modern web pages using a P166 w/ 128MB RAM)...
d) I'm not really sure what measuring VM is telling you? A combination of working set and private bytes are much more informative IINM (process explorer terminology).
The benefits from moving away from IE and its shells from a technical perspective are numerous. IE/Maxthons engine is ancient and showing its age. It renders slowly, has poor support for modern technology and innumerable bugs that are constantly worked around. Lots of modern pages add in additional hacks to get IE & shells working, which will add to its overhead. Performance of IE and Maxthon are poorer in many areas than modern engines (though tables in IE are fast (popular 5 years ago for web layouts), CSS is poor (popular for newer pages).
So I *do* think there are clear advantages with regards to "effective" resource utilization to move away from IE and its shells, and other advantages too.
I've done tests on history memory - using 10 pages of navigation through 3 google image searches in different pages for "picasso", "magritte" and "dali" (20 images per page = 600 images in 30 pages total). IE fails on page switching after a few back navigations, forcing a redraw and uses more memory than opera. Firefox has a 5 page limit (thus fails half of the instant-back operations) and uses the most memory. Opera allows instant-back for ALL pages using ~25MB less private bytes than IE and ~35MB less private bytes than Firefox. I find that pretty impressive... http://my.opera.com/...ndpost.pl?id=1789849