The Dawn of Haiku OS (Spectrum)

Posted Apr 29, 2012 20:07 UTC (Sun) by tialaramex (subscriber, #21167)
In reply to: The Dawn of Haiku OS (Spectrum) by cmccabe
Parent article: The Dawn of Haiku OS (Spectrum)

Haiku doesn't actually have a "hybrid" kernel, whatever that means. It's just a simple monolithic design like Linux. BeOS had some nods to microkernel architecture, putting the TCP/IP stack and sockets layer into a userspace server. But that worked out very badly for them, the performance was lousy and the traditional "a socket descriptor and a file descriptor are really the same kind of thing" trick from Unix didn't work, nor was there a workable replacement (as there is in NT based systems). So by the time Be Inc ceased to exist it was well known that the company intended to put networking inside the kernel, and Haiku follows this approach today.

The Dawn of Haiku OS (Spectrum)

Posted Apr 29, 2012 20:48 UTC (Sun) by drag (guest, #31333) [Link]

> a "hybrid" kernel, whatever that means.

A hybrid kernel is created using 1 of 2 methods:

Method 1:

A proprietary software company advertises operating system uses a microkernel as if it is a big selling point. Then you have a huge slew of fanboys that by into such advertising unquestionably and then touts that feature as evidence of the technical superiority of their consumer product of choice. Then more knowledgeable people point out that it's not actually a microkernel at all and it damages the reality distortion field. To repair the reality distortion field people then go out and write articles on wikipedia and various other places about hybrid microkernel kernel design.

The Dawn of Haiku OS (Spectrum)

Posted Apr 30, 2012 7:03 UTC (Mon) by danieldk (guest, #27876) [Link]

In fact, the leaked Dano (R6) builds had a BSD-based networks stack in the kernel.

The Dawn of Haiku OS (Spectrum)

Posted May 2, 2012 1:02 UTC (Wed) by cmccabe (guest, #60281) [Link] (1 responses)

tialaramex said:
> Haiku doesn't actually have a "hybrid" kernel, whatever that means

I was quoting wikipedia. From http://en.wikipedia.org/wiki/Haiku_(operating_system):
> The Haiku kernel is a modular hybrid kernel and a fork of NewOS,[4] a
> modular kernel written by former Be Inc. engineer Travis Geiselbrecht.
> Like the rest of the system it is currently still under heavy development.
> Many features have been implemented, including a virtual file system (VFS)
> layer and rudimentary symmetric multiprocessing (SMP) support.

To be honest, I have no idea which parts of Haiku are implemented in kernel space and which in user space. It would be nice to see a list somewhere.

The Dawn of Haiku OS (Spectrum)

Posted May 5, 2012 13:28 UTC (Sat) by tialaramex (subscriber, #21167) [Link]

It's roughly the same split as Linux. So for example, most hardware drivers live in the kernel, but printer drivers (because they don't really do anything directly with hardware) live in userspace just like a typical Linux distribution. The low-level bit banging graphics hardware drivers live in the kernel, but code for drawing windows and so on lives in userspace. Similarly for audio the software mixer lives in userspace while the hardware drivers live in the kernel, the same split as any modern Linux distro (this is true even though Haiku uses OSS drivers, for which the mixer is usually in the kernel) Filesystems live in the kernel, but they have looked at implementing FUSE. Networking lives in the kernel, including both drivers and the TCP/IP stack.

If you ask one of the people actually /working/ on Haiku's kernel about this they don't care. The "hybrid" claim comes from the fanbase, not the developers. To remove the claim from Wikipedia you'd need an authoritative third party source to say it isn't true, and in topics like Haiku there's a lack of such sources... Unfortunately, being able to "cite" Wikipedia, you will see this claim spreading, and then those recitations can be cited on Wikipedia, snowballing. As I said, for an important topic someone would step up and fix this, but for fans making a bogus technical claim about a hobby OS it's unlikely to happen. Genre claims for obscure bands (e.g. claiming some band "invented" a genre years before it was popularly recognised) are likewise subject to fan distortion on Wikipedia.