Semi-OT: NVidia XRENDER support (was Re: [Xr] Graphics board for working with XRENDER)

Owen Taylor otaylor at
Tue Jun 10 19:24:48 PDT 2003

On Tue, 2003-06-10 at 20:25, Jim.Gettys at wrote:
> For most things, Render won't be the bottleneck.
> If you read the latest gtk2 release notes, for example, you'll see a
> note about small strings being 5X (!) faster in this release.
> And if you look at the traces from Keith's and my Usenix paper
> of this year, you'll see both GTk and Qt are doing some amazingly
> dumb things still....

There tends to be a lot of problems with NVidia and RENDER -
we've had reports of incorrect rendering and drastically poor
performance with GTK+, not because of poor support, but to
an extent because of "good" support .... the NVidia proprietary
drivers try to accelerate RENDER and basically nothing
else does. (There's some simple acceleration in the mga driver,
but it's pretty much completely disabled for XFree86-4.3.0
because it was buggy.)

As Jim says, most of the time, RENDER isn't the bottleneck, so
even with the current pretty slow software path, no acceleration 
isn't a problem. But if you try to accelerate then there is
the opportunity for bugs.

RENDER will become more of a bottleneck, I think, as Xr or
the like starts to be heavily used.


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