upgrade from ubuntu 10.04 to Jessie on multiboot?

For your dual core processor you can follow the instructions outlined here.
forum.linuxcnc.org/forum/18-computer/259...s?limitstart=0#27492
and
sudo add-apt-repository -y ppa:danielrichter2007/grub-customizer
sudo apt-get install grub-customizer
Open grub customizer
In the general settings add to kernel parameters
quiet splash lapic noxsave -original paramters- intel_idle.max_cstate=0 processor.max_cstate=0 isolcpus=1 acpi_irq_nobalance noirqbalance

Did this help? let me know.

I'm still waiting for my Mesa board.

Once it arrives and I have it set up, I'll check the latency with and without what you outlined above.

If I did it now, I would just have to do again when everything is up and running anyway. I don't have the luxury of putting in the time just to satisfy my curiosity right now.

I appreciate the info and all your work, and will try it once I'm up and running. I've also been monitoring the 14.04.1 installation thread where you have been active regarding 64 bit.