(I have worked as an engineer on both Ubuntu and Chrome)
> One tab on chrome takes about 100MB memory, why?
It probably doesn't.
Much of that apparent memory usage is shared between all tabs, and the browser renderer process, etc. in the form of shared memory.
Quite a bit of it will be the executable code itself, which is "mapped" into memory, given an address, and allocated the full size but doesn't actually consume memory until it needs to be read from disk.
And a large part of that memory is going to be the giant white pixel buffer that you want it to draw into, which is typically mapped to a texture buffer in the GPU memory.
> One tab on chrome takes about 100MB memory, why?
It probably doesn't.
Much of that apparent memory usage is shared between all tabs, and the browser renderer process, etc. in the form of shared memory.
Quite a bit of it will be the executable code itself, which is "mapped" into memory, given an address, and allocated the full size but doesn't actually consume memory until it needs to be read from disk.
And a large part of that memory is going to be the giant white pixel buffer that you want it to draw into, which is typically mapped to a texture buffer in the GPU memory.