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Comment by baq | Hacker News Reader

for rebooting, you'd have to have super-fast POST and device initialization after power cycle, so i wouldn't say milliseconds.

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Definitely. Most of my Dell machines take 2-5 minutes to get to the "booting OS" part of the process, but a couple of them have at times taken 3 hours.

The latter is probably a firmware bug, but the best Dell ProSupport has been able to do to solve it is "flea drain" (unplug, hold the power button for 60 seconds, plug back in).

Dell servers are notoriously slow to boot, but this is due to the remote management subsystem being extremely slow.

It's quite a pain in the arse, and one of the reasons we prefer to use Supermicro machines for development at work, using only Dell for testing.

The aerospike demo Intel did at the event showed 17 seconds vs over 2000 seconds for a restart. The difference being rebuilding a dram index on a many many terrabyte data set. Remembering aerospike has consistency, so you can't have the index be slightly wrong.

He doesn't mean rebooting will take microseconds/nanoseconds, he means the transaction commit will take that long. Before, a transaction commit meant flushing disk, at least as far as the disk controller. Now, commit = memory barrier.

"What that enables is powering down servers that aren't being used with the ability to power them up in milliseconds rather than seconds." (great-grandparent)

Actually and "restarting". Technically it isn't "booting" because the OS is already in memory and initialized, it just isn't running.

Given your typical motherboard which you tell to bypass POST, it can go from power applied to memory controllers alive in just a few microseconds. The code then to go from there to running is also quite small, especially if there aren't things like graphics controllers on the PCI bus that have to be initialized first.

And even those can probably be lazy-loaded, with a page fault in the IOMMU and handled as soon as the rest is done, or the rest isn't doing anything and something is thus blocking on the GPU initialisation.

At least we've been moving glacially in that direction, thanks to UEFI & faster booting. POST, device initialization, etc has begun to stick out, and is slowly being improved.

You can write your own custom firmware and skip the unnecessary bits.

close your laptop lid, wait 10 seconds, open it up, did it resume quickly?

2017 MacBook Pro 15". No, it doesn't. Open the lid, time passes before screen is no longer black. Even longer amount of time before the TouchID figures out my finger is the accepted finger. So, when did it resume? When the screen lit up, or when I could actually use it? Obviously, Apple's TouchID is preventing me from resuming, but to the user, that's all they care about.

You made the choice buying Apple.

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