2.4 kernel problem

[David Ashley <dash@xdr.com>]

XFree86 X window updates are slower on 2.4 than 2.2, by a significant amount.
I've observed this comparing 2.2.18 with 2.4.1 and one of the 2.4.pre kernels.
I've seen it with ATI Rage 128, Geforce 1 and GeForce 2 MX. I've seen it on
two different computers, both Athlon based. Just any rectangular copies to
an X window are slow on 2.4 and much faster under 2.2.18.

I'm using DRI and accelerated GLX servers so I get good 3d, but 2d is
suffering in a *big* way. Here are some frames/second for a simple program:


Using shared memory       Kernel       frames/second
     yes                   2.4              39
     no                    2.4              30
     yes                   2.2.18          245
     no                    2.2.18           88

I can't get any response from the XFree86 team. I know I'm not the only
one with this trouble, something has been broken in the 2.4.

Thanks--
Dave
dash@xdr.com