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Benjamin Herrenschmidt On PPC/Linux, Apple and OSS
MacBoy writes "The folks over at ResExcellence have a great interview with Benjamin Herrenschmidt, kernel guru for the PPC/Linux camp. He offers up some history of Linux on Apple and PPC hardware, and some discussion on Apple's current and past contributions to the open-source and Linux communities. He makes some interesting comparisons of Linux on PPC vs. Intel hardware, such as the ease of getting important patches into the kernel on PPC compared to Intel. It's an interesting read, especially if you are amoung the many who covet the new Dual-CPU GHz G4 Macs and want to know a little more about the PPC/Linux community."
PPC/Linux seems like an ambitious and technically interesting project, no doubt. Personally, though, I don't seem to understand the purpose. MacOs X is based on BSD, so you get all the nice Unix-like server features... and a decent GUI, something that Linux has never had. Are there some other advantages of Linux/PPC that I'm missing?
If guns kill people, then CmdrTaco's keyboard misspells words.
I was going to ask if anyone has Linux running on the new dual G4's, but then I found this cool link
http://linuxppc.org/hardware/dualg4/
Anyone have benchmarks (under Linux) for the dual G4's and corresponding PCs for:
- compiling the kernal
- GIMP
- Quake1/2 benchmarks
I'd love to get the "other endian machine" and compile some game code on it. Anyone have any recommendations? How did id do the Quake3 port to Macs ?
"PC Expert - Mac newbie"
Despite the early antagonism between the league for programming freedom and Apple, Macs and Unix went together pretty well. Long before samba, 680X0 Macs were sharing files quite nicely with unix servers. In many disciplines at universities, unix was used for heavy lifting, and macs were used for light word processing and making drawings.
Linuxppc has benefited from the generally better hardware on the PowerPC (higher quality and reliability, and less diversity). Also, for much of the '90s, the PPC chip was faster for many things than ix86. Recently, I had a 90 MHz powermac running KDE, xemacs, and Netscape without a hitch for months without any hiccups (a little slow but definitely useable). Under MacOS the thing would lock up several times a day. OS X is not an option for these older macs.
My old Mac died but I hope to get an ibook soon and put Linux on it. By the way, I wish there was something like fips for shrinking Mac partitions for people that want to dual boot.
The lmbench numbers show that linux is significantly faster for certain operations. I have a copy of the results that I pointed to in an old post over here. Linux spanks OS X. It's a reason.
Other reasons include access to all of the source of your OS and better support for certain things (pcmcia 802.11b card support? Better filesystems. More software already working).
I personally run Debian on my laptop 99% of the time because my environment is the same everywhere, and apt-get kicks ass (fink on OS X is cool, but there isn't as much stuff available).
Of course, the long-standing debate between Mac and Windows (I use the term generally) users has been that of their respective platform's performance. Sure, Max users complain that Windows is ugly, Windows user complain that Mac OS doesn't have enough apps...BUT, the big ticket is always when they start comparing Intel (or AMD) processors to their PPC competitors.
With Linux on both platforms, I would be interested to see some comprehensive real-world benchmarks comparing the two platforms. Really, I'm rather tired of the "Megahertz-myth" PPC touters and the "RISC sucks" x86 campions arguing which is better without any solid numbers.
-Jayde
What's a sig?
When (and only when) each instruction takes one clock cycle to execute you can divide each instruction inte several sub-tasks, for example Fetch - Decode - Execute - Store. Now a pipeline can be introduced:
instruction 1 F D E S
instruction 2 . F D E S
instruction 3 . . F D E S
instruction 4 . . . F D E S
In this way work is parallellised. Four instructions are executed in parallell, during 4 clock cycles each, giving a throughput of 1 instruction per second.
CISC basically means that instructions take different number of clockcycles to execute. With such an instruction set you can not use Pipelining.
The i386 cpus today transform the CISC instructions into RISC instructions, and apply pipelining. For the price of a translator the major drawbacks with CISC are avoided.
It is probably true that Intel has to put more research and silicon into a CPU than Motorola to achieve the same performance. But this is not because Intel are stuck with building a CISC cpu - it is because Intel must emulate the i386 CISC instruction set on a RISC cpu core.
With OS X the usefulness of Linux on the PPC platform is indeed brought into question, but article is still a good read.
It's interesting, however, to note that Linux people still miss the whole point of finding out about Mac OS X. Don't like it? Don't use it. But if you're smart you'll develop for hit. Read the O'Reilly Network, or any any other article, for writing in cocoa for MacOS X.
If there's anything missing in the viability of the comments about PPCLinux and its "questionable viability" you could well say the same thing about Linux in general as a desktop platform. It's going nowhere. Genome and KDE will not only never be the finished GUI that OS X is, but they also won't have the installed (and growing) desktop users that OS X has either.
New games are shipping for OS X, not ports, but original games. The recent O'Reilly network article about writing for cocoa represents an idea which any geek interested in making a living doing something besides tweaking SQL databases may want to consider.
Sure, the Mac OS X kernal, Darwin, itself offers much to users. But any Linux geek who likes to write code should give it even more serious consideration, its portability to other platforms, including Linux.
If you're hung up on the idea of free software disregard this, but if you're looking for a good *nix OS check out OS X if you're smart.
Linux is often faster. Just like Intel Linux, it's possible to create a custom stripped down desktop with no fat. I've become accustomed to how things work on my Intel Linux machines and like having almost the same environment on my Pismo Powerbook. I also prefer the GNU utilities over the BSD ones (flame away...it's just a preference...get over it).
OSX is also next to useless on older hardware. We use 233Mhz Beige G3 desktop as an internal server. It's running ssh, Apache-SSL, NTP, mySQL, Apache, and Netatalk. The Apache/mySQL setup powers our troubleticket/inventory system. The Netatalk/Samba combo makes files available to both Mac and Windows clients. It does all of this with very acceptable speed and reliablity. The machine has zero need for a GUI...and doesn't have one. I suppose I could use Darwin but the machine wouldn't do it's work any better and I would have to mess with fussy ports of the daemons. It has full apt-get goodness....I forgot to mention that it is dead easy to admin.
So yeah, there are valid reasons to use Linux on PPC hardware.
I had a little trouble getting all of the modules to work with one of his 2.4.17rc kernels. I figured what the hey and emailed him. He straightened me right out. I suppose the world of PPC Linux is small enough that a leading light can have a little time for an end user like me.
Lets forget about OS-X for a moment. What LinuxPPC does is fix the mac by providing a real operating system for it. There are macs where I work, and every time I'm stuck using one I start getting crazy notions in my head about taking a sledge hammer to them all, or finding some other way of destroying them. The reason has nothing to do with the hardware they are running. They're not super fast, but I'm not particularly picky in that area. What bugs me about them is the antique operating system they're running. If I wanted cooperative multi-tasking and no memory protection between apps, I'd run windows 3.1. When I sit down in front of a computer I expect the system to be responsive to me, regardless of what it is doing in the background.
One day about a year ago I loaded up the PPC version of SuSE 7.0 onto one of the macs. Lo and behold!!! A new computer was born! Or at least it seemed that way. The computer actually seemed to run FASTER as well as being infinitely more responsive. I was also a great relief to escape from the Macs GUI, which I find cumbersome. It was like I was trying to run with a cinder block tied to my leg and someone just cut the cord. Unfortunately I eventually had to wipe Linux and reinstall MacOS-9 on it.
Nowadays we have OS-X, which is about 6 years late, but better late than never. Its GUI isn't on par with KDE, but its far better than the previous MacOS versions. Its also responsive! Its great to actually be able to have my computer wait on me rather than the other way around. Its not terribly fast, but I'm not going to complain! Much better that it take longer to do things in the background but be more responsive in the foreground than it lock me out. Hopefully IBM/Motorola/Apple will be able to push the PPC architecture further in terms of clock rate.
Then of course there are the standard form-factor PPC motherboards that will soon be available. Whether they will ever outperform an Athlon based system is doubtful, but the fact that they are there and available is a good thing.
Lee
Muslim community leaders warn of backlash from tomorrow morning's terrorist attack.
Nothing against OSX, but in all honesty even a fully loaded Linux desktop will take less RAM than OSX. I'm running a fully loaded KDE right now, with Mozilla (rumor says it's bloated), StarOffice 6.0, and Kmail, and my used (not cache) memory is only at 64MB. Note that only KDE and Kmail share many libraries.
I don't know where people get this idea that you need a ton of memory to run these programs. Granted, 128MB is little on the high side if you're talking real low end, but these are desktop workstations, as you said. OSX requires that 128 at a bare minimum, and even that maxed out when I was using 10.0 (don't know if they decreased the RAM requirements as of 10.1, but I doubt it). Linux apps just don't take as much memory as people say. KDE gets you a solid UI with a lot of bells and whistles for relatively low memory cost. Plus, the inclined desktop user could simply run fluxbox or twm, which isn't possible without Darwin, in which case you can't easily switch to Aqua. OSX is great, but Linux has its advantages too.
"I may not have morals, but I have standards."