why did Ubuntu turn off kernel preemption in Edgy?

Jan Claeys lists at janc.be
Tue Nov 28 19:00:11 GMT 2006


Op dinsdag 28-11-2006 om 12:02 uur [tijdzone -0500], schreef Phillip
Susi:
> While 500ms is too long, I thought that the brain could not notice sub
> 100 ms of latency, certainly not 32 ms. 

Considering that a human brain can unconsciously detect the difference
between 65 Hz (flickers for most people) & 75 Hz (doesn't flicker for
most people) CRT screen refresh rate, why wouldn't it be able to
(unconsciously) detect a 100 ms latency?  65 Hz means that pixels get
lighter and darker a bit inside every 15 ms interval.  75 Hz means that
pixels get lighter and darker a bit inside every 13 ms interval.

Similarly, I think that maybe (most) people don't hear the latency
difference *consciously*, but it might still be irritating them because
what's played when they press a key is just a tiny little bit off the
right beat that they intended it to be on.

-- 
Jan Claeys




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