ARM multiprocessor support | Hacker News Reader

ARM multiprocessor support

blog.netbsd.org

76 pointsfcambus16 comments

While welcoming this, it's amazing this kind of thing is news. That so many communities failed to acknowledge the inevitable rise of SMP systems still amazes me. This blind spot basically killed OCaml, which has fantastic single thread performance, and it remains a serious problem for things like Python.

The same thing is now happening with the rise of GPGPUs.

There are many more ways to concurrency and parallelism than threads.

> That so many communities failed to acknowledge the inevitable rise of SMP systems still amazes me.

What? NetBSD most certainly didn't fail to acknowledge the inevitable rise of SMP systems. These boards lacked SMP support because SMP support is a lot of work, every chip is different (unlike x64), very few people know how to work on this, there are very few people working on the NetBSD kernel, and most chips don't have open documentation.

You make it sound like these people were like "SMP... shit, who needs this?".

I would love to run a *BSD as my daily driver on my X220, but battery life is important to me and everything I've read suggests that most BSDs don't perform as well as Linux + TLP,

I run Net on my t420, and I like it. I feel like I get ~3 hours (I don't keep hard time) using it, and it'd be fair to say typical use is development, w/ web (ie: running X, vi, clang, and various text-processing tools, Firefox, and disk/network intensive things like syncing code-repositories).

I've got a 9-cell battery.

I'm running -current. Now that -current is also offloading rendering to my integrated i915 gfx, I'll be curious to see how screen-intensive work will impact battery.

The joy I get from NetBSD has outweighed various temptations from other OSes. I've dabbled w/ Ubuntu and others, but they're not compelling enough to switch.

If you've got any questions, I'm happy to try to answer.

Your 9 cell is probably knackered. I get about 7 hours out of mine and its two years old.

What OS/power-management are you running ?

FreeBSD 10 r10 stable with some ACPI frigs and dpms set up (I didn't write them down)

Windows 8.1 Pro with Lenovo power manager installed via windows update.

Dual boot.

New battery en route --- I'll be able to tell first-hand what the differences are in a week or so :)

Good for you :)

I would check the Lenovo recall page (google it) before paying for one. That's where I got my new one from - they replaced it free of charge ;-)

>If you've got any questions, I'm happy to try to answer.

I'm not really a leet haxor when it comes to fiddling with driver power management and configs. I like linux because I can just fire up powertop and manually switch the config settings to the ones that TLP doesn't flip automatically.

Did you have to do a lot of hacking and do you know if openbsd is comparable in terms of power management?

My X201 is fine with FreeBSD. in fact the battery life is slightly better than windows 8.1. Hibernate doesn't work so I just shut it down.

Performance isn't an issue really even though its an i5. If it is too slow, I ship the problem elsewhere (the feck off great big 24 core E5 HP Z620 in the office).

Sure there may be 10% difference between BSD and Linux but that's negligible these days versus the positives (like being able to just pkg install ruby21 without having to bugger around with rvm or wait three years for debian to pick it up in stable)

I am disappointed not to see any of the Beagle* boards on the list of supported devices, as it is another ARMv7 device with completely open hardware. Still, this is a pretty cool consolidation effort.

The beagle{bone,board} use single-core OMAP3 derivatives; they don't require multiprocessor support and were already supported.

Other boards will undoubtedly get support over time.

Every single board requires a different setup, often times dtb, special boot loaders or u-boot, special kernels, etc. Give it time.

Wandboard will be exciting once they support that.

http://www.wandboard.org/index.php/details

I'm still looking for a decent OS for my U3 [1], and last time I checked BSDs were not a (serious?) option.

1: http://hardkernel.com/main/products/prdt_info.php

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