Gosh

Posted Sep 14, 2011 16:23 UTC (Wed) by khim (subscriber, #9252)
Parent article: LPC: Coping with hardware diversity

David started with a brief note to the effect that he dislikes the "embedded" term. If a system is connected to the Internet, he said, it is no longer embedded. Now that everything is so connected, it is time to stop using that term, and time to stop having separate conferences for embedded developers. It's all just Linux now.

Is it really good to start the keynote with the bogus statetement and then spend the rest of keynoted explaining why exactly said statement is bogus?

To embed: to set solidly in or as if in surrounding matter the nails were solidly embedded in those old plaster walls

Embedded OS (Linux or any other) is an OS which is tightly tied to hardware and where OS replacement is not supposed to happen without vendor involvement. Which pretty much describes all ARM devices on the market - connected or not. Sure, there are few devices (such as Nexuses from Google) where end-user is given the ability to install new OS, but even there this OS should be fine-tined for one particular device.

ARM devices are embedded systems - and that's exactly the problem which we are discussing here. This is what sets them apart from PC or Mac. To say that the fact that devices are connected somehow makes somehow OS non-embedded... gosh.

Gosh

Posted Sep 14, 2011 17:34 UTC (Wed) by k8to (guest, #15413) [Link] (6 responses)

Traditionally embedded refers to the computer being embedded in something else. For example, computers in a car. Granted, people use it often now to refer to things like smart phones and game consoles, which are entirely computers.

I submit that the word barely means anything anymore.

This may be so, but difference is still meaningful...

Posted Sep 14, 2011 18:09 UTC (Wed) by khim (subscriber, #9252) [Link]

Perhaps, but then perhaps not. From the software developer POV difference between XBox360, Android phone and, for example, TV is pretty minimal. In all cases you can install your own custom firmware, in all cases this is not something developers had in mind at all.

Now, you can argue that computers were initially developed in such a way (back then software was just a free addon to the hardware), but what we now understand under this term is some box where hardware is developed for the software, not the other way around.

ARM systems are slowly moving in this direction, too, but they are still pretty much at stage where development is driven by hardware, not the other way around.

Gosh

Posted Sep 14, 2011 19:22 UTC (Wed) by nhippi (subscriber, #34640) [Link] (4 responses)

I think k8to and khim end up underlining the original point - "Embedded" is not useful word, it means different things to different people. I would subscribe closer with k8to's definition. A computer system (hw +sw) becomes "embedded" when something else than the computer system is the important bit.

Better use more clear terms:

General purpose / singe purpose system
High performance / limited performance system
Wall powered / Battery powered (power managment critical)
Qwerty and mouse / Limited input options
Big screen / small or no screen
Generic hardware / Tailored hardware

Traditionally all of the "right side" have been lumped together as "embedded" systems, but in reality most systems are mix of features from both sides.

Consider Juniper routers which have x86 and FreeBSD but the really important stuff is the custom routing hw attached to the system. High performance single purpose machine with couple of leds and buttons.

Alternatively a Android tablet built on tegra2 reference design is general purpose system (you can install apps for almost any purpose and browse web for more), high performance (well depends what you compare to), battery powered, complex multitouch input support and a screen with resolution we used to have our PC's not a long time ago (1280 x 800).

Lumping both under "embedded" does not really help anyone.

Gosh

Posted Sep 15, 2011 7:34 UTC (Thu) by alison (subscriber, #63752) [Link] (2 responses)

I concur with Gosh completely.

Thanks as always to Corbet for a fascinating post about what sounds like a fascinating presentation. My respect for Rusling and Linaro continues to grow. When I heard that Linaro was mostly Canonical-funded, I was suspicious, but I was completely wrong.

Gosh

Posted Sep 15, 2011 14:29 UTC (Thu) by james_w (guest, #51167) [Link] (1 responses)

Linaro isn't Canonical-funded, it's funded by these people:

http://www.linaro.org/members/

Gosh

Posted Sep 15, 2011 17:52 UTC (Thu) by wookey (guest, #5501) [Link]

Indeed. Linaro was/is canonical-bootstrapped (as a good way to get an engineering organisation going quickly). I've no idea how the money works but it is probably either neutral or going the other way (for the use of all their kit and engineers).

On the 'embedded' point, I have to disagree with khim. ARM is not all systems you never change the OS on, and even to the extent that that is true (a lot of random and fairly closed consumer kit) it's still the wrong way to think about it. ARM is just another architecture, like intel x86 and MIPS, and you can make whatever sort of computer you like out of it. Early ARM machines (when I got started in early 1990s) were full desktop machines, driving monitors, with harddrives and having plug-in keyboards. And we are about to see a lot more of that sort of thing with ARM servers, arm laptops, arm netbooks, home servers etc. Thinking of it as a 'mobile phone/embedded' arch is already behind the times.

There is already loads of ARM kit out there which is 'a real computer' and there is no reason why you shouldn't change the OS if you want to (although you may not have a very wide choice of non-linux OSes in practice).

To me 'embedded' was when you had 8K of RAM and 4 IO wires to play with - these days microcontrollers are much bigger than that and anything that can run linux has enormous resources in comparison.

[Disclosure: I've been working on arm kit since 1993 and am currently working for Linaro at ARM].

Gosh

Posted Sep 15, 2011 11:39 UTC (Thu) by jone (guest, #62596) [Link]

Language is use .. which is probably why Wikipedia and vigilance serve as a better dictionary these days than Oxford.

I think your first item is more accurate as systems should really be looked at as:
General Purpose/{Single, Limited} Purpose

As we've got devices going both ways .. Like i used to say of cameras, the most useful computing devices are the ones you have on you - so as I see it - you've got much of the small mobile market attempting to become General Purpose these days, and in the high end space - we've really got the reverse in many places as ppl are attempting to do more single/limited things closer to the hardware with general purpose servers and workstations.

Not every ARM == embedded

Posted Sep 15, 2011 13:23 UTC (Thu) by hrw (subscriber, #44826) [Link]

On my desk I have few ARM based computers: PandaBoards, Efika MX Smartbook, BeagleBoards. Each of them is running same operating system (Ubuntu), none of them has OS fine-tuned except of kernel and x11 drivers (which is a case on PC too).

Also have other ARM systems which I would not call embedded as I can run Debian on them.

But I also have (small) experience with embedded x86 systems which OS was done in fire-and-forget way which is common to embedded market regardless of CPU architecture.

Too many Linux conferences

Posted Oct 5, 2011 16:01 UTC (Wed) by davidarusling (guest, #80637) [Link]

Thanks for the comments. Just to explain myself a bit.

-- Conferences ---

As we're consolidating ARM contributions, we're also pushing at various bits of kernel infrastructure, the memory management stuff, for example. To do the right thing (i.e., end up with the right code in the kernel) we need agreement from a wide range of open source communities (kernel, multimedia, video etc). Going to many, many kernel conferences is not terribly efficient.

I think that this is a scaling problem for the Linux kernel engineers; what forums make sense to attend in order to agree designs, code, directions? Whilst presentations are good for bootstrapping knowledge, I'm more interested in technical decisions being made. Linux plumbers is one such conference, but only happens once a year. Whilst Vancouver was good, it could have been better.

--- Embedded ---
For me, traditional embedded is low memory, tight timings. Disk controller fits pretty well. Thinking of ARM as embedded is limiting, as it is no longer just embedded. Thinking of ARM as just another architecture is also misleading, because the drivers and business models are fundamentally different.

Dave