Re: a joint letter on low latency and Linux

[Bill Huey]

Cory,

> Can you characterize what you mean by extensive?  You can do FP in
> RTLinux.  If you're going to be doing heavy computation you're not going to
> want to hold the cpu in RTLinux and should ship the data off to a
> user-level task to do the number crunching.  Do you need to respond to an

Pushing it to as high a CPU useage as possible. ;-) The more a CPU can be
dedicated to doing signal processing the better. And I agree that this stuff
should be in user space.
 
> event, in realtime, and provide a response (that requires FP) within a
> given interval?

That an other evil stuff that's best kept in a single space, preferabley user
space, so that all of it and can be modified on the fly. Adjustment of DSP modules,
various kinds of timing, fairly complicated event models, etc... 

> It does do SMP.  In fact, we've had good numbers from kicking Linux off a
> processor and doing just RTLinux on it.  Can you characterize what exactly
> you need RTLinux to do with regard to SMP for you?  If so, we can tell you
> if it can or can't do it :)

I haven't been keeping track of this feature of RTLinux and I assumed that
little has change since a year or two ago.

bill