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Everything Else => Zaurus Distro Support and Discussion => Distros, Development, and Model Specific Forums => Archived Forums => Angstrom & OpenZaurus => Topic started by: GadgetGuy on May 12, 2006, 01:39:22 pm

Title: Why Is Oz Not Using Flash On The C3100?
Post by: GadgetGuy on May 12, 2006, 01:39:22 pm
Hello all,

is there a specific reason for this?

If I install OZ on my C3100 today, it actually turns it into a C3000, with its lower flash size and higher power consumption...

Is there any benefit having a C3100 vs. the C3000 when using OZ?

THanks for any comments,

Miklos
Title: Why Is Oz Not Using Flash On The C3100?
Post by: koen on May 12, 2006, 01:41:45 pm
Quote
Hello all,

is there a specific reason for this?

If I install OZ on my C3100 today, it actually turns it into a C3000, with its lower flash size and higher power consumption...

Is there any benefit having a C3100 vs. the C3000 when using OZ?
[div align=\"right\"][a href=\"index.php?act=findpost&pid=126761\"][{POST_SNAPBACK}][/a][/div]

Running from microdrive is a lot faster as running from flash, since you don't have to g(un)zip every bit before using it.
Title: Why Is Oz Not Using Flash On The C3100?
Post by: GadgetGuy on May 12, 2006, 01:53:18 pm
Quote
Running from microdrive is a lot faster as running from flash, since you don't have to g(un)zip every bit before using it.
[div align=\"right\"][a href=\"index.php?act=findpost&pid=126763\"][{POST_SNAPBACK}][/a][/div]

Thank you for the quick response: I was not aware of this...

Can I still use the flash to store data in it? How?

Thanks again,

Miklos
Title: Why Is Oz Not Using Flash On The C3100?
Post by: ShiroiKuma on May 12, 2006, 01:54:52 pm
Quote
Quote
Hello all,

is there a specific reason for this?

If I install OZ on my C3100 today, it actually turns it into a C3000, with its lower flash size and higher power consumption...

Is there any benefit having a C3100 vs. the C3000 when using OZ?
[div align=\"right\"][a href=\"index.php?act=findpost&pid=126761\"][{POST_SNAPBACK}][/a][/div]

Running from microdrive is a lot faster as running from flash, since you don't have to g(un)zip every bit before using it.
[div align=\"right\"][a href=\"index.php?act=findpost&pid=126763\"][{POST_SNAPBACK}][/a][/div]
So what happens with the 120 Megs of flash now. It's not used for anything?
Title: Why Is Oz Not Using Flash On The C3100?
Post by: TheWalt on May 12, 2006, 02:41:31 pm
Quote
Running from microdrive is a lot faster as running from flash, since you don't have to g(un)zip every bit before using it.

I also like it because you can have a very large root if you wanted for easier package installs.  If I knew this was coming earlier I'd have saved the money on the 3100 and just got a 3000, but thats me.
Title: Why Is Oz Not Using Flash On The C3100?
Post by: lpotter on May 12, 2006, 02:45:49 pm
Quote
Running from microdrive is a lot faster as running from flash, since you don't have to g(un)zip every bit before using it.
[div align=\"right\"][{POST_SNAPBACK}][/a][/div] (http://index.php?act=findpost&pid=126763\")

I believe you are wrong about NAND being slower than disk.
from this article titled "Hard-disk drives vs. flash"

[a href=\"http://www.eetimes.com/showArticle.jhtml?articleID=177103404]http://www.eetimes.com/showArticle.jhtml?articleID=177103404[/url]

"NAND devices, by contrast, are smaller, more robust, require less power and have some speed and performance advantages over disks."
"NAND flash offers much lower latency times and much greater I/O operations per second. "

Spinning that disk takes heaps of energy also. There's a reason why they put 128 mb NAND on that device.
Title: Why Is Oz Not Using Flash On The C3100?
Post by: GadgetGuy on May 12, 2006, 03:08:59 pm
Quote
Quote
Running from microdrive is a lot faster as running from flash, since you don't have to g(un)zip every bit before using it.
[div align=\"right\"][{POST_SNAPBACK}][/a][/div] (http://index.php?act=findpost&pid=126763\")

I believe you are wrong about NAND being slower than disk.
from this article titled "Hard-disk drives vs. flash"

[a href=\"http://www.eetimes.com/showArticle.jhtml?articleID=177103404]http://www.eetimes.com/showArticle.jhtml?articleID=177103404[/url]

"NAND devices, by contrast, are smaller, more robust, require less power and have some speed and performance advantages over disks."
"NAND flash offers much lower latency times and much greater I/O operations per second. "

Spinning that disk takes heaps of energy also. There's a reason why they put 128 mb NAND on that device.
[div align=\"right\"][a href=\"index.php?act=findpost&pid=126783\"][{POST_SNAPBACK}][/a][/div]


You have not read koen's answer carefully. He said, that flash is slower because the data is compressed on it. Reading and decompressing is slower than reading not compressed from the harddrive...
Title: Why Is Oz Not Using Flash On The C3100?
Post by: Mickeyl on May 12, 2006, 04:29:09 pm
Quote
So what happens with the 120 Megs of flash now. It's not used for anything?

Right. It isn't. Speak up, when you have any idea for how to use it.
Title: Why Is Oz Not Using Flash On The C3100?
Post by: koen on May 12, 2006, 04:36:31 pm
Quote
Quote
Running from microdrive is a lot faster as running from flash, since you don't have to g(un)zip every bit before using it.
[div align=\"right\"][{POST_SNAPBACK}][/a][/div] (http://index.php?act=findpost&pid=126763\")

I believe you are wrong about NAND being slower than disk.
from this article titled "Hard-disk drives vs. flash"

[a href=\"http://www.eetimes.com/showArticle.jhtml?articleID=177103404]http://www.eetimes.com/showArticle.jhtml?articleID=177103404[/url]

"NAND devices, by contrast, are smaller, more robust, require less power and have some speed and performance advantages over disks."
"NAND flash offers much lower latency times and much greater I/O operations per second. "
[div align=\"right\"][a href=\"index.php?act=findpost&pid=126783\"][{POST_SNAPBACK}][/a][/div]

That would be true if you were using yaffs(2) on mtd or ext2 over mtdblock, but with jffs2 it will be slower. Another factor is the slow NAND interface on the cxxxx.
Could anyone do some basic benchmarks like dd'ing a big file (/dev/zero > file and file > /dev/null) and doing some (semi) random access to small files?
Title: Why Is Oz Not Using Flash On The C3100?
Post by: adf on May 12, 2006, 10:44:15 pm
Quote
Quote
So what happens with the 120 Megs of flash now. It's not used for anything?

Right. It isn't. Speak up, when you have any idea for how to use it.
[div align=\"right\"][a href=\"index.php?act=findpost&pid=126800\"][{POST_SNAPBACK}][/a][/div]
A place to store some sort of backup?  critical files and and a script to manage ipkg (and maybe formatting and partitioning) as a way to thoroughly restore a hosed system? this would be something useful, but not needed...a small bonus for 31 and 32 owners.
Title: Why Is Oz Not Using Flash On The C3100?
Post by: wylbur on May 17, 2006, 02:16:36 am
after I flashed OZ/Opie 3.5.4.1-rc2, I found that for reasons I don't know, there are four partitions in the NAND. First I tried to look at the partitions:
Code: [Select]
root@spitz:~/books# fdisk /dev/mtdblock
Unable to open /dev/mtdblock
Then I tried to mount the first and second partitions:
Code: [Select]
root@spitz:~/books# mount /dev/mtdblock0 /mnt/nand0
mount: Mounting /dev/mtdblock0 on /mnt/nand0 failed: Permission denied
root@spitz:~/books# mount /dev/mtdblock1 /mnt/nand1
mount: Mounting /dev/mtdblock1 on /mnt/nand1 failed: Invalid argument
Ok, I'm root, so I don't quite get the permission denied error. Are these the famous backup images? Anyway, I was able to mkfs.ext2 -j /dev/mtdblock{2,3}, and now I have the following:
Code: [Select]
root@spitz:~/# df
/dev/mtdblock2           31729      4127     25964  14% /mnt/nand2
/dev/mtdblock3           88243      4127     79560   5% /mnt/nand3
My plan is to store stuff that I don't want overwritten during OZ flashes to /mnt/nand2 and /mnt/nand3. Similarly, I've moved /opt and /usr/local to links on /dev/hda3 (mounted as /home), and I figure that will be safe too.

Am I right, OZ developers?

TIA, and for all the great work -- wylbur.
Title: Why Is Oz Not Using Flash On The C3100?
Post by: Cresho on May 17, 2006, 02:59:57 am
The real question is...

if they are not using the internal flash drive, why not flash kde or ubuntu.?
Title: Why Is Oz Not Using Flash On The C3100?
Post by: JohnX on May 17, 2006, 07:52:36 pm
Quote
The real question is...

if they are not using the internal flash drive, why not flash kde or ubuntu.?
[div align=\"right\"][a href=\"index.php?act=findpost&pid=127400\"][{POST_SNAPBACK}][/a][/div]

GPE/matchbox have a lot of tuning to look nice on small screens and have light memory and CPU requirements. I think that's the reason that most people choose to stick with GPE/matchbox even when there are alternative desktop environments (like KDE or GNOME). As for Ubuntu...Does Ubuntu have an official ARM port? If it does have an ARM port that has good support for Zaurus specific features and hardware, it would probably be easiest to use their tools to install it.  If there is an ARM port, but no real official Zaurus specific support (like Debian) it would probably be easiest to use a chroot (like you're doing already). Maybe I'm misunderstanding the question?
Title: Why Is Oz Not Using Flash On The C3100?
Post by: Mickeyl on May 18, 2006, 08:44:24 am
I guess I gave a lenghty answer in a different thread...
Title: Why Is Oz Not Using Flash On The C3100?
Post by: Da_Blitz on May 19, 2006, 03:46:03 am
The perms problem may be related to the wierd mtd stuff that has 2 device nodes per partion, one being RO the other being RW