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On Wed, 15 Jul 2009, Rob Beard wrote: > Gordon Henderson wrote: >> >> So how can they get the entire kernel startup to a second?!? If I could >> get power-on to /sbin/init down to under 10 seconds I'd be extremely >> happy... >> > As far as I know (after watching the demo video) they use an > uncompressed kernel with only drivers which the hardware requires and > use DMA access to transfer the stuff into memory, I gather too that the > hardware is pretty limited due to it being designed for in-car use. > > It also says that it has to be able to withstand the power being cut. > > I dare say that if it was to do other stuff other than the single task > it's designed for then it would probably take longer to boot. Indeed - Now I could put an uncompressed kernel on my units too, and possibly even an uncompressed initrd - although I suspect they are running out of a live flash device at that point. Copying a kernel from flash into RAM still takes time - unless they're running the flash as RAM.. Even so, my kernels are compiled exactly for the hardware - no modules. Actually a bit too 'exact' as I don't include drivers for USB or the hardware crypto devices on-board. Surviving a power cut is relatively easy too - my PBXs do it, although they do have a live ext2 filesystem on them - the boot side of things is wholly static. It's still impressive, and I'm jealous! Gordon -- The Mailing List for the Devon & Cornwall LUG http://mailman.dclug.org.uk/listinfo/list FAQ: http://www.dcglug.org.uk/linux_adm/list-faq.html