Thread: Safari 4 Beta; the worlds fastest web browser...

blade5x, no matter how fantastic your computer is, different software will always perform differently. It's also higly relevant whether the browser uses a lot of power. Browser developers could easily make the fastest browser ever. Problem is, it requires 1GB free RAM, a 3GHz dual-core processor and a CUDA compatible GPU and operating system.
What browser developers aim for, is good performance with less hardware usage. I.E. FireFox has always been wellknown for stupid memory leaks, where its RAM usage would just slowly rise higher and higher. That's why browser performance is relevant, even if you have a good computer.

Originally Posted by Marvo

I.E. FireFox has always been wellknown for stupid memory leaks, where its RAM usage would just slowly rise higher and higher.

ram usage did indeed creep up and up on windows, but this was nothing to do with memory leaks in firefox

Wasn't the bug only happening in FireFox? I mean sure, maybe it wasn't doing that on Linux, but if it's doing it on Windows and no other browsers are, then it's a memory leak.

The problem was Windows's memory management
the issue specifically is memory fragmentation

When you load a webpage, it typically loads lots of images as well
these images are compressed (Jpeg, Gif, Png, etc.)

In order to use a webpage properly, these images have to be uncompressed, and sit in memory for the duration of the pages life

You have to store them uncompressed, else when you scroll a page (or any action that changes a page) the images would flicker as they are redrawn from their compressed states

A webpage can potentially take up many megs in memory due to large quantities of images being stored as uncompressed bitmaps

So, you have an initial "high memory usage" issue to start with

As you are navigating around a website, some images drop off (because they're only on one page) while some stick around (as they are present on all pages)

the various smilies and user avatars & sig pics are present on some pages, but not all
whereas the top banner on this site, and various style images are present on all pages

So, when you first view a page on a website, the memory is filled up with stuff

a bit solid block of used memory

then you move to a different page, and some memory is freed up as images drop off, while some cannot be as they're still needed

moving around a website will split up the memory block as new images may be too big to fit in the freed-up holes or the OS memory manager just chooses not to reuse previously freed memory

20 pages into the site, the memory block looks like a swiss cheese
there's a whole heap of "free'd" memory, but it's in small clumps dotted all over the place

An OS will report an application is "using" memory if it's been previously allocated but not taken back

Windows was reporting that Firefox was using more and more memory, purely because the Windows memory manager was not smart enough to deal with all these small scattered blocks of free memory

The OS did not reclaim the memory, so Firefox is still "using" it (even though it's been free'd)

All browsers on windows (as far as I know) suffered from this,
but Firefox seemed to be most affected due to the way it implimented it's page caching

Originally Posted by Ynot

The problem was Windows's memory management
the issue specifically is memory fragmentation

If I recall correctly, some newer browsers use idle time to try and slowly defragment memory, correct?

I honestly don't know
(does anyone outside MS?)

Many *nix OS's use SLAB allocation, developed by Sun in 1995
http://en.wikipedia.org/wiki/Slab_allocation

SLAB combats memory fragmentation in a number of ways

Linux used an implimentation of Sun's SLAB allocator from 1999 - 2007
I know about 2 years ago, most Linux distros migrated over from the SLAB allocator to the newer SLUB allocator

This reduced memory fragmentation issues even further
http://lwn.net/Articles/229984/

Windows. No clue

but in any case, it's an OS issue not an application issue

I just installed it on my Macbook, it really is faster than chrome in all of my benchtest.

It does look suspiciously like Chrome though. I guess Apple decided that they've been ripped off so many times, it was time to do it to someone else