lsorense@csclub.uwaterloo.ca wrote:
On Fri, Aug 05, 2011 at 04:07:06PM +0000, Phil Endecott wrote:Hi Steve, Steve McIntyre <steve.mcintyre <at> linaro.org> writes: > Hi folks,> > We've got a number of discount vouchers for theseToo late for me... > We're about to purchase a number > of these for buildds for the Debian armhf portHmm. Are you sure it's the best choice? It has a single Cortex A8 (like the old Beagle Board). The Panda Board has a dual Coretex A9. I've not benchmarked them, but I would expect the Panda to be a lot faster for CPU-bound tasks. The iMX53 has the advantage of SATA if you expect to be I/O limited, but if I were building a "farm" I think I'd seriously consider NFS and negligible local storage.make + NFS = nightmare in many cases.
Well I use NFS almost exclusively for everything every day, and I've never experienced any "nightmares".
You do need to have time synchronised everywhere. I use ntp.
My choice of the iMX53 was based mainly on its video features (it has analogue VGA out, which the Panda doesn't) and more than a bit of prejudice because I seemed to be the interested only person at CELF last year who didn't get a free Panda.Anyway, if you do go with the iMX53, do keep us informed. I'm currently working on mechanical/electrical things e.g. a box and power supply. Note that the board seems to have very little capacitance on its 5V power input, so it can "brown out" if you connect something (via USB or otherwise) that has non-trivial inrush current. There is also the fact that it powers-on "off" until you press a button, which I imagine is probably not the behaviour that you'll want.I was wondering how their power control is done. Obviously a SATA drive would need external power.
I've chosen to use an SSD in part because it requires only 5V, so you can just fork from a single 5V PSU to the board and the SSD. I believe (but am not certain) that 2.5" HDDs also don't need 12V. Although the SATA power connector also has pins for 3.3V, nothing currently uses them. There doesn't seem to be a problem with applying the power to the drive before the board is on; anyone building a product would want to check the SATA specs and see if this is officially condoned.
Regards, Phil.