On Sat, Aug 23, 2014 at 11:20 PM, Brandon Vincent
<[log in to unmask]> wrote:
> On Fri, Aug 22, 2014 at 9:41 AM, <[log in to unmask]> wrote:
>> Does it really make difference in timing control comparing to non-realtime
>> kernel? Thanks.
>
> Whether or not you need a RTOS depends on your specific needs. Since
> you're working with LabVIEW, I would check out their white paper on
> the subject.
>
> http://www.ni.com/white-paper/14238/en/

I assume you're running real hardware, instead of virtual systems?
I've seen people try to run "real-time" systems in virtuaalized,
CentOS based VMware systems, and the results for extremely low latency
operations were not encouraging. I also spent a lot of time with that
with CentOS 5 making sure the hosted partitions were 4096 byte block
aligned, which made a *big* difference with NetApp backend disk image
storage.

>> I don't have NI's realtime system but I am looking for a free linux OS which
>> supports realtime kernel. So I wonder does anyone have experience in
>> this on scientific linux? Does it support realtime kernel?
>
> NI Linux Real-Time is based off of the PREEMPT_RT patch set which you
> can find on the kernel.org Wiki.
>
> https://rt.wiki.kernel.org/index.php/CONFIG_PREEMPT_RT_Patch
>
> I've never compiled an EL kernel with the patch, but there is no
> reason why it should not be possible.
>
> Brandon Vincent

If you go this route, do look into creating kernel RPM's with the
"mock" toolkit and with patches applied as part of the SRPM. It's
extra work to start with, but lets you manage the kernels and report
dependencies more effectively.