Intel's Linux Driver Sees Async Flipping Patches For Better Performance

[coder]

Still, page flip is pretty basic stuff. SVGA cards used to have these same techniques some 25 years ago. It's one of the main things I remember from the merry old DOS days and mode 13h & VBE graphics programming. The >320x200 performance would badly suck without efficient page flips.

I'm just speculating, but the fact that iGPUs are using system memory could complicate matters, slightly. Also, the hardware block that does rasterization and shading is different from the display engine. In short, it's probably not so basic--this ain't your father's VGA card.

You could probably find the patch, if you wanted more insight into what's involved and why it's taken so long.

Edit: from looking at the commit message (linked from article), it didn't seem to touch too many lines or files. However, we don't know how much groundwork had to be put in place, in order to enable it.

[brent]

Even then, the case for such an optimization @ 4K is more one of energy-efficiency & laptop battery life.

With DDR4-2666 memory, 1.5 GB/sec only amounts to about 3.6% of total memory bandwidth. So, it's not a big win, but I have a laptop with an Intel iGPU and will certainly welcome the change.

Many laptops - even newer ones - still use LP-DDR3 RAM though, with clocks as low as 1866 MHz. Sometimes even only a single channel. Besides, there's more to it than memory bandwidth: Intel iGPUs also have severly limited fill rate. This is as much about performance as it is about energy efficiency.

[ms178]

And why would that be the case? They'll never sell as many dGPUs as they already sell iGPUs, and the folks using dGPUs tend to upgrade them more frequently.


Oh, that kind of support. Don't care.

Because NVIDIA and AMD set the standard here, both having driver support for multiple generations as far back as eight years now. Half of that just isn't competitive. This is even more important as technology advancements stalled during the last decade.

[coder]

Many laptops - even newer ones - still use LP-DDR3 RAM though, with clocks as low as 1866 MHz. Sometimes even only a single channel.

Such laptops would have 1080p screens or even lower. So, it's still going to be just a couple %.

It's obviously an improvement, but just tweaking around the margins.