On Fri, 2004-07-16 at 04:33, Malcolm Baldridge wrote: > > Some of these fixes were to > > extremely important areas (get_user_pages, a fix for > > framebuffer-scrolling issue, and more). > > It goes against common sense (to anyone with kernel knowledge) to use the > console framebuffer anyway. > > The duration of kernel locks and the CPU expense of blowing bitmaps around > like that are shocking. > > Seriously. Use text-mode consoles, or a native AGP-driver a la nvidia, ati, > or whatever. But using a "stupid" framebuffer driver is asking for hardcore > latency blow-outs. > I am using text-mode consoles, and switching back and forth between those and X using ctrl-alt-F[1-7]. I sent Andrew Morton some XRUN traces and he said one of them was caused by framebuffer scolling inside lock_kernel(), and the fix was to remove (un)lock_kernel() from do_tty_write(). This particular fix may not be in -mm1, because he seemed to think it would cause problems (display corruption, etc). It has not caused any problems for me. Maybe I am confused about the 'framebuffer' vs. a text-mode console, I thought they were the same. Anyway, the point is, switching from X to a text-mode console and back caused XRUNS before, and now it doesn't. Lee
