>Anyone got a URL or otherwise for what the difference is between 
>pre-empt and low-latency patches?  I know they are good, but should 
>I apply both, one or the other, or is there some other worthy patches.
>Laymans explanation for what is pre-empt or low-latency??

Great article on this that i was reading the other day :

http://www.linuxdevices.com/articles/AT8906594941.html

Basically, these patches try to decrease the time that applications have to
wait to respond to IO.  This is important for things such as sound/video
processing, where you have 
large amounts of data coming in that must be moved/processes lest you loose
it.  

What normally happens is your application requests some data from an IO
device, and the kernel says "OK, I'll get that for you, go to sleep so i can
do something else and I'll wake you up when I'm done".  The kernel requests
the data from the IO device, and goes on doing something else.  When the
device is finished, it sets an interrupt to signal that it's done and the
data is ready.  In normal linux, the time between your application being
woken back up and given this data is extremely variable, and not suitable
for things like serious audio work.  In a real time OS, the time between the
interrupt and your application getting woken up would be constant.  With
these patches, it makes it somewhere inbetween.

The consequence for normal users is that people report the system feels
"snappier" to use as it responds to their requests faster, so you might find
it good.

-i
[EMAIL PROTECTED]
http://www.wienand.org


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