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Capn_Fish
First off, this is an honest question, NOT an attempt to start a flame war. I REALLY want to like Debian on my Zaurus.

What makes Debian so much slower than Angstrom? They both run off of the HDD and they both use EABI (?), so why the huge performance gap? Is it something I could fix?

Thanks.

PS: Is there a way to have a Debian-Angstrom dual-boot? I know at least for a while Debian was using the Angstrom kernel.

EDIT: Nevermind. I decided that my Angstrom build environment was foobared enough, as were the images, so Debian gets another chance. I'd still like to know why it's slow, though.
axeTail
QUOTE(Capn_Fish @ May 12 2008, 04:09 AM) *
First off, this is an honest question, NOT an attempt to start a flame war. I REALLY want to like Debian on my Zaurus.

What makes Debian so much slower than Angstrom? They both run off of the HDD and they both use EABI (?), so why the huge performance gap? Is it something I could fix?

Thanks.

PS: Is there a way to have a Debian-Angstrom dual-boot? I know at least for a while Debian was using the Angstrom kernel.

EDIT: Nevermind. I decided that my Angstrom build environment was foobared enough, as were the images, so Debian gets another chance. I'd still like to know why it's slow, though.


Hi Capn_Fish,

Are you running titchy? I've installed zdevils rootfs, with the yongguns kernel and it's fast.
Capn_Fish
Nope. I'm running the Yonggun kernel with the rootfs referred to above, and things take several seconds to load (even Rxvt).

EDIT: OK, maybe not several seconds, but a few.
mikeones
QUOTE(Capn_Fish @ May 12 2008, 11:41 AM) *
Nope. I'm running the Yonggun kernel with the rootfs referred to above, and things take several seconds to load (even Rxvt).

EDIT: OK, maybe not several seconds, but a few.

Speed is the same here. I figured it was normal on the arm arch.
matthis
I am running debian from the internal microdrive on my sl-c3200. I thought the delays were due to the fact that the microdrive is slow...
Capn_Fish
Angstrom runs from the MD, and it is much faster.
JohnX
A couple differences I can think of (off the top of my head) that might affect this:
-CPU specific gcc optimizations in Angstrom vs standard lowest common denominator Armv4t optimizations in Debian
-Angstrom often builds things without options that aren't typically used on a handheld, where Debian typically includes all options
-Lots of fine tuning to reduce memory usage, such as reducing the number of services run by default
-ash/busybox vs bash/coreutils

Overall, this is why for day-to-day stuff I boot angstrom from SD and for when I *need* something from Debian I boot it from a usb-stick.
Capn_Fish
Ahh, that would make sense.
Capn_Fish
How hard is it to get a build setup to rebuild the repos (or at least a more condensed version) with armv5te optimizations? I have a comp that I could dedicate (1GHz Via C7, 250GB SATA HDD, 1GB RAM) to the build, if it meant a faster Debian (Angstrom has me ticked off ATM wink.gif).
judecn
The SD card reader on the C-series is a serious bottleneck in my experience. The internal flash is faster, giving Angstrom et. al. the appearance of being faster. Also, with Debian, programs are bigger (as mentioned above, they are more featureful), so loading/unloading data from storage will naturally take longer anyway. However, in my experience, EABI programs in Debian run about as fast as their Angstrom counterparts once loaded into RAM.

If you are using a GUI, by far the biggest bottleneck with responsiveness is anti-aliasing. If you can turn it off (if your GUI even supports it), you will notice a HUGE speed boost. In fact, with XFCE on my Debian zaurus, the difference in speed before and after is about an order of magnitude.
Capn_Fish
Angstrom runs from the MD on Spitz.
JohnX
Cross compiling will be harder than native compiling. Someone apparently did ubuntu builds specifically targetting different ARM processors ( mojo.handhelds.org ), but they used a build farm of ARM machines, IIRC and/or qemu-arm-system on x86 machines. qemu is an option for you, but you'll probably end up with slower compiles than on a real zaurus. That being said, profiling certain programs and/or libraries and recompiling them with fewer options or CPU optimizations might make a big difference in some cases.
domi007
You can try crosstool.
It can download all the things you need for cross-compile. It has a specific script for intel-xscale processors.

DOMy
Capn_Fish
I will have to look into that. Thanks much!
radiochickenwax
QUOTE(domi007 @ Jun 19 2008, 06:54 PM) *
You can try crosstool.
It can download all the things you need for cross-compile. It has a specific script for intel-xscale processors.

DOMy



Any pointers to a zaurus/cross-tool "how to"?
Capn_Fish
http://www.kegel.com/crosstool/

That ought to do it.
dlj0
QUOTE(Capn_Fish @ May 13 2008, 07:43 AM) *
Ahh, that would make sense.


Well, it would make sense were it true. But the debian kernels kicking around for the Z are not full-featured with lots of things you don't need on a Zaurus, but are specifically compiled for the Zaurus. In fact, I seem to recall that at least some of them _were_ Angstrom kernels. All the scripts are set up specifically for the things you would want on your Z as well, so IIRC there were not a bunch of extra services or logging.

Frankly, my experience was that debian was essentially the same speed as Angstrom. Now, maybe I whittled down some memory hogs, such as blacklisting the sound modules since I didn't use them (maybe that's part of it), and used a lightweight window-manager (I used xfce4 and, later, icewm).

The biggest differences were the ease of upgrade and availability of packages, both strongly in favor of debian.
Capn_Fish
My system is about as lean as I can make it, and it still feels slower than Angstrom. I'm still thinking that the difference in optimizations may be the cause of it.
scottlfa
I found that Debian on the Z is noticeably slower than some custom distro's for the Z such as PdaXrom. Though it is close to PdaXrom R198-SP8 in speed, I am thinking the speed edge there is nand vs sd card related. Your choice of WM matters alot and services etc that are running when the system loads.

I use rcconf to control load up of service from the console and presently use E17 as my wm (though lxde is pretty light too).

Been using Debian basically since I was first able to muddle through the install process.
Capn_Fish
I would agree with you, but Angstrom also runs from the internal MD, and it was fine with no slowdown.
scottlfa
Still consider angstrom to be a Z specific distro (may need to change my opinion of it), where as debian arm is for a broader base of devices and not optimized for the Z. So too me a side by side would be partially hampered.

JMO.
scottlfa
Tried Angstrom again ... and nothing seems to have changed, various issues that I would consider very unpolished in the feeds. Faster yes, more useful ... not for me ... ymmv but having no preset apps and going to the feeds just to get the basics is for the birds.

I admit speed is an issue with debian eabi, but its reliable and comes set with linux basics at the get go. Recently tried Andromeda EABI and it seems significantly faster than the basic eabi I was using. It was a breeze to install and the lxp wm is light enough to be very responsive. Apps load in a reasonable time frame too. Just an update smile.gif
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