Ubuntu's LPIA-based MID Edition Can Save 10%+ Power
Phoronix: Ubuntu's LPIA-based MID Edition Can Save 10%+ Power
When it comes to putting Ubuntu Linux on mobile devices, Canonical has two flavors of their popular Linux distribution to suit the needs of vendors and end-users: Ubuntu Netbook Remix and Ubuntu MID. The former targets netbook computers (hence its name), particularly those with Intel Atom processors, and brings a unique interface atop GNOME. The Ubuntu MID edition is targeted for very small netbooks and mobile Internet devices. Particularly, Ubuntu MID aims to be on handheld devices and those with 4-7" touch-screens. Beyond having a different user interface, Ubuntu MID is spun with LPIA packages instead of the i386 package-set. LPIA is quite similar to i386, but targets the Low-Power Intel Architecture with different compile-time optimizations. With the low-power focus, will this distribution extend your battery life? Yes, our results today show that the power consumption can be cut down by greater than 10%.
Well, that clears up what LPIA is useful for. thanks!
What makes it special? Just recompilation with different CFLAGS, or is it more than that?
I hope the phoronix benchmark team realizes that the Moblin alpha 2 release has a TON of expensive kernel debugging options enabled (as is suitable for an alpha release) and that they will disable these for their benchmark..
Arjan - who works for Intel on Moblin
Originally Posted by arjan_intel
Yep, I am aware of that, though the benchmarks don't do really bad at all on Moblin. The results that should be out early next week show both Ubuntu NR/MID and Moblin competing well with a few tests in each distribution's favor. Once Moblin V2 is out of development, I would be happy to run the tests again.
Any ideas what the performance tradeoffs are for the LPIA mode optimizations?
I'm not sure your analysis is correct.
The MID release is targeted at computers with very low resources, 128MB of RAM, for example. The applications installed on it, including the window manager, the web browser, and the file browser, are all very light weight in comparison to the equivalent apps on the UNR distribution. I don't think that comparing memory consumption between these two releases says anything about how well Linux does (or doesn't) do when compiled for lpia. I bet that if I were to switch to a lighter weight window manager than gnome and a lighter weight browser (such as the MID browser), I would see memory consumption improvements with the i386 software, too.
There is an alternate install CD for the lpia architecture at http://cdimages.ubuntu.com/ports/releases/9.04/beta/. If you want to compare lpia to i386, you should probably install from that ISO and apply the UNR configuration to it. After all, no one would run the MID edition on their netbook for longer than it takes to reconfigure it so that the interface is usable on the netbook.
So this lpia is just some fairy dust sprinkled over a linux distro? I cant find a technical desciption of what lpia is or how to get it (ewww?) anywhere.
Okay here's the culprit:
Last edited by bnolsen; 03-31-2009 at 06:46 AM.
LPIA is Low-Power Intel Architechture. If you use the prior nomenclature they used at Intel, it really ought to be IA-LP.
Originally Posted by bnolsen
I'm pretty sure there's a bit more to it than those settings. GCC probably doesn't target the whole range of optimizations needed to actually "target" the LPIA microcode type of x86 machines, based on that link you provided. It's interesting that they're reccomending -O3 (I wouldn't in all cases...) as well as using the Nocona optimizations.
Hehe...that's the hand wavy description. I really want details since I run gentoo (and I use an n330 running 64bit as a workstation). I also have an acer aspire one that's running arch linux.
Originally Posted by Svartalf
Well being pretty sure is pretty hand wavy again. The link I found there was posted by an intel employee for their suggested LPIA compile flags. I did some searching and came up with nothing more.
Originally Posted by Svartalf
I'm speculating the nacona is a more basic architecture than the core2 with less reliance on out of order optimizations, which may incidentally run better on the in order atom.