Intel Q35/Q45 fb driver?

McDonald, Michael-p7438c Michael.McDonald at
Tue Oct 6 10:26:22 PDT 2009

Although this isn't directly related to X11, I'm hoping someone here
might know if there's a fb driver for the Intel Q35/Q45 chips? We're
currently using X for our app but the overhead of moving all of the data
is killing us, performance wise. Essentially, we're doing

  while (1)

as fast as we can. Using RHEL5.3 on a 2.66GHz Q35 box, we get 23
frames/sec, which is almost acceptable. (A 2.4GHz Dell/nVidia Quadro NVS
285 gets 78 frames/sec.) Once we run a hypervisor/separation kernel
under RH on the Q35, we get a whooping 3 frames/sec! That performance
isn't acceptable.

So we're trying two different prongs of attach:

1) change the MIT SHM extension to use mmap() instead if SYSV shared
memory so we can map our source images directly in the X server, getting
rid of several extra copies.

2) get rid of X and copy the images directly into the framebuffer. This
requires a fb driver that supports the Q35/Q45 chips, which I haven't
been able to find.

Any pointers would be appreciated. Or suggestions on a different
approach to solving our issues under X.

BTW, we're in 1680x1050x24 mode.

Mike McDonald

More information about the xorg mailing list