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by tostitos1979 3545 days ago
Very cool stuff! Some boards, like the beaglebone, have specialized hw like PRUs or I2C pins. Is it possible to access these with Docker containers? Also, what is the minimum memory footprint? i.e. how many containers can I fit within say 1 GB.
1 comments
alexandros 3545 days ago
The version of Docker on the OS right now is 1.10 so the ram footprint of the OS is fairly small. The team is all asleep (being in Berlin and whatnot), but I'd estimate about 50mb is a decent approximation. We're working on getting a newer Docker but its RAM footprint is one of our concerns, though we do have ways forward.

The number of containers is kinda a red herring for a couple reasons. For one, you can make a trivial container and launch as many containers as you like, it really depends on what's in them. For another, embedded devices don't usually need hundreds of containers, they run payloads that are either single-container, or look a lot more like a docker-compose file with a few microservices.

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amorphic 3545 days ago
You missed this part of the question: "Some boards, like the beaglebone, have specialized hw like PRUs or I2C pins. Is it possible to access these with Docker containers?"

I'm really interested in the answer also!

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alexandros 3544 days ago
I don't think resinOS affects that either way, but I will check and come back to you in a few hrs as the team in Europe wakes up.
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ohstopitu 3545 days ago
quick question...would the images have to be specifically built for arm? (we were looking to build a cluster of RPis that we could orchestrate containers on.)
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alexandros 3545 days ago
Yes. We build many container base images for all architectures. have a browse and pick what works for you -- https://hub.docker.com/r/resin/ and also http://docs.resin.io/runtime/resin-base-images/
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djsumdog 3545 days ago
ARM isn't x86. You get a nice generic kernel with enough built in drivers plus an Initrd and it can boot on most Intel/AMD hardware both old an new (at least the Pentium 4+..maybe even the P2 or P1. Haven't tried a newer distro on them).

ARM isn't anywhere near as standardized. There are usually vendor kernel patches, not just for drivers, but dependent on the block layout of that particular ARM board. uBoot is often forked and also specialized. There is no one shoe fits all Grub.

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lifeeth_ 3545 days ago
Yes - they would have to be built with ARM base images.
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