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Comment by sieve1234 | Hacker News Reader

I doubt that. I know there is research in sensor network (e.g. at my university) and they say they want ulta-small low-power devices but the experiments I have seen were never in need of that much small devices.

Of course there are applications were you want to go really low-power/extra-small, but in that case even a micro-controller capable of running Contiki OS is too big. What I want to say is, that the application space where you can't deploy a small machine with Linux on it BUT it is feasable to have a small machine with Contiki on it is pretty narrow.

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I guess there's always some wiggle room on most deployments. However, where I used to work, some of the guys at that department were conducting research on flying foxes as their migration patterns southern to northern parts of Queensland (Australia) were pretty much unknown (IIRC). The requirements there gets pretty tough. Also, the power consumption becomes a major factor as it will limit the amount of useful work the device can do, ie sensing, communication etc.

Anecdote: I learned about another project where they studied opossums. They put a collar with a small wireless device around their necks to track their movements and habits, but couldn't understand why a disproportionate amount of opossums died for some reason.... The reason was that the device had a small red LED that would blink to indicate that it was working, and the opossum, being a nocturnal animal became quite visible in the night, to the joy of all predators :) :S

That's really funny because something similar was done at my unversity (I think with bats, or maybe even flying foxes). I declined because although the devices were really small and they assured me that the animals did not come to harm I doubted that. It's like carrying around a big backpack.

This is getting OT, but sensor network applications and discussions often neglect the problem of device recovery and I know there are projects were sensors are not recovered and after they did their work (sensing stuff and sending it to a post-processing node) they go out of energy and become ... highly toxic waste.

Looks like there's a huge difference between small Linux and something like Contiki. Any time you run out of on-chip SRAM without an MMU (e.g. anything really low power) Linux is not a good fit. That non-Linux space is gigantic and there's room for something like Contiki as well as much lighter systems that have some form of non-IP networking. We evaluated a bunch of small kernels (ended up with uc/OS) but there are dozens of open and proprietary kernels that fit specific needs both larger and smaller than Contiki that are non-Linux for good reasons.

Yeah, uClinux is what i'm used to for MMU-less platforms. Then there's RTOSes, where you're looking at VxWorks/QNX/LynxOS for commercial support, or RTLinux/FreeRTOS/ChronOS for something unsupported. The Raspberry is a neat platform with plenty of uses, but custom tailored electronics often have exotic hardware with unique software constraints.

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