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robbika
06-04-2003, 05:30 PM
I have noticed that now it is possible to get USB flash memory up to 1 Gb.

Although it would be very very expensive at the moment, is it technically feasible to boot Knoppix from an external USB flash memory?

Is USB 2.0 flash memory speed fast enough, and would it be faster than from CD-ROM?

garyng
06-05-2003, 01:14 AM
1x CD is 150KB/s so 50x would be 7.5MB/s, USB 2.0 is 480(?) Mb/s or 60MB/s. Putting overhead aside and assume the flash can reach that speed, yes. However, none of the off-the-shelf flash can have that speed. It would be at best comparable but I guess in general slower if the claim of 48x CD is real(that I have no idea).

BTW, I am thinking along the same line but instead of 1GB, I am aiming at the 256M CF which is very cheap nowadays. A trim down KNOPPIX can fit into it and there would still be some space for persistent home. The only problem is machine supporting USB booting is still not the majority.

aay
06-05-2003, 05:08 AM
Here are a few links to consider the speed of cf as well as mmc and sd cards.

http://www.dpreview.com/articles/mediacompare/
http://www.davespda.com/hardware/expansion/cfmmcsd.htm
http://www.amazon.com/exec/obidos/tg/guides/guide-display/-/1QVQAXJGTBBWI/ref%3Dcm%5Fbg%5Fdp%5Fl%5F2/102-6952374-5295339

The general concensus seems to be that cf is the fastest of these three media, but that even it is not as fast as a cd.

Getting Knoppix to run off of this media should be possible as long as your bios supports booting from usb. However as some of the posts at knoppix.net indicate you will have to tweak things because Knoppix is set up by defalut to expect to see itself mounted on a cd.

What's interesting about this approach is not so much the speed of CD's vs the speed of CF cards but rather the fact that you can write to a CF card.

If you do intend to write to it then you will either need to shrink Knoppix, or get a really big CF card (3GB is the largest I've seen) since Knoppix is compressed.

reub2000
06-06-2003, 12:32 AM
It would be at best comparable but I guess in general slower if the claim of 48x CD is real(that I have no idea).

48X claim is only on the edge of the disc. Also, at less than a dollor, a cd is a lot cheaper than flash ram.

You could look at some of the lighter remasters, copy the cloop compressed file, then boot via a bootfloppy (if the floppy searches the flashram, I don't know), and see if it works.

elgaard
07-18-2003, 10:56 AM
[quote="aay"]
> However as some of the posts at knoppix.net indicate you >will have to tweak things because Knoppix is set up by >defalut to expect to see itself mounted on a cd.

I dont think so. Knoppix tries to boot any /KNOPPIX directoty on a SCSI mountable drive.

--
Niels

zhrinze
08-06-2003, 08:25 AM
It would be at best comparable but I guess in general slower if the claim of 48x CD is real(that I have no idea).

48X claim is only on the edge of the disc. Also, at less than a dollor, a cd is a lot cheaper than flash ram.

You could look at some of the lighter remasters, copy the cloop compressed file, then boot via a bootfloppy (if the floppy searches the flashram, I don't know), and see if it works.

While it's true that a CD is cheaper, I can build a computer with *no* moving parts once the CD is transferred to compact flash. Further, the power consumption of a laser is higher.

There's a $600 computer complete with case that is Linux friendly and for $30 you can purchase a CF reader that plugs into the IDE adapter on the motherboard. You only cost then is the CF itself. While expensive, I can run it all day with very little power. Of course I can do this with any version of Linux. An install version of Knoppix would be great for this.

drboo
08-13-2003, 04:53 PM
I have had this dream for a while myself. Has anyone been able to find substancial data on how many bios's these days support USB booting? I'd love to have a 256Mb keychain drive with a bootloader and some small versions of livecds for different hardware (x86/PPC/Sparc)

Pjotr
08-17-2003, 05:17 PM
1x CD is 150KB/s so 50x would be 7.5MB/s, USB 2.0 is 480(?) Mb/s or 60MB/s. Putting overhead aside and assume the flash can reach that speed, yes. However, none of the off-the-shelf flash can have that speed. It would be at best comparable but I guess in general slower if the claim of 48x CD is real(that I have no idea).

BTW, I am thinking along the same line but instead of 1GB, I am aiming at the 256M CF which is very cheap nowadays. A trim down KNOPPIX can fit into it and there would still be some space for persistent home. The only problem is machine supporting USB booting is still not the majority.

A typical Flash disk speed is about 2-3x USB 1.1. So you are talking about 1 MB/s for USB 1.1 flash disks and no more than 2-3 MB/s for USB 2.0 flash disks.

However, many people have already made USB flash disk bootable Linuxes, from 16 MB and up. Devices above 256 MB costs more than the size increase.

Pjotr
08-17-2003, 05:20 PM
I have had this dream for a while myself. Has anyone been able to find substancial data on how many bios's these days support USB booting? I'd love to have a 256Mb keychain drive with a bootloader and some small versions of livecds for different hardware (x86/PPC/Sparc)

Only the modern motherboards supports this. If you take an average hobbyist computer, I'd bet it doesn't support it. If you want to build computers with this function, you can easily find motherboards today.

Don't build a distribution that uses the USB disk for frequent writing. Flash devices supports about 1 000 000 write cycles during their lifetime. This may sound much but in reality is very little. If your OS runs from the USB like a HD, you will burn out the USB flash disk quickly. So stick to only writing few times, like saving configs etc. Use RAM disks for runtime info.

reub2000
08-18-2003, 09:59 AM
It would be at best comparable but I guess in general slower if the claim of 48x CD is real(that I have no idea).

48X claim is only on the edge of the disc. Also, at less than a dollor, a cd is a lot cheaper than flash ram.

You could look at some of the lighter remasters, copy the cloop compressed file, then boot via a bootfloppy (if the floppy searches the flashram, I don't know), and see if it works.

While it's true that a CD is cheaper, I can build a computer with *no* moving parts once the CD is transferred to compact flash. Further, the power consumption of a laser is higher.

There's a $600 computer complete with case that is Linux friendly and for $30 you can purchase a CF reader that plugs into the IDE adapter on the motherboard. You only cost then is the CF itself. While expensive, I can run it all day with very little power. Of course I can do this with any version of Linux. An install version of Knoppix would be great for this.

No moving parts? What about a cpu and psu fan? And maybe a northbridge fab?

Zentesis
08-24-2003, 08:32 PM
In my opinion it’s possible.
I have a Pen Stick of 256Mb. The Knoppix lite have a 208Mb. The “only problem“ is that we find a booteable floppy that it allow boot with the Pen Knoppix.
Anybody know anyone? :?:
Is true the problem of write 1 million times but the advantage will be enormous.
You imagine all the students that in theirs colleges or universities don’t have own theirs computer. All owns configurations (desktop, mozilla, etc.) go with them. But no only the students, the cybercoffee or airport terminals will have a USB connect and you have your computer in your pocket. :D
The advantages for the administrator is clear, because how the computer don’t have a hard disk, the people don’t break the system.
The second requirement is a post it in the monitor whit your own IP and the gateway.
:wink:

garyng
08-25-2003, 02:04 AM
In my opinion it’s possible.
I have a Pen Stick of 256Mb. The Knoppix lite have a 208Mb. The “only problem“ is that we find a booteable floppy that it allow boot with the Pen Knoppix.
Anybody know anyone? :?:
Is true the problem of write 1 million times but the advantage will be enormous.
You imagine all the students that in theirs colleges or universities don’t have own theirs computer. All owns configurations (desktop, mozilla, etc.) go with them. But no only the students, the cybercoffee or airport terminals will have a USB connect and you have your computer in your pocket. :D
The advantages for the administrator is clear, because how the computer don’t have a hard disk, the people don’t break the system.
The second requirement is a post it in the monitor whit your own IP and the gateway.
:wink:

That is my vision too and not just student but my view about future computing(like phone booth on the street with my computer(the hd/CF) in my pocket).

As for a boot floppy for usb, assume the support for usb reader/drive is getting better, it is pretty easy. just change the miniroot.gz to include usbcore.o, usb-storage.o usb-ohci/usb-uhci and load them in the linuxrc script before KNOPPIX do the 'where am I scanning'. need to remove some of those scsi driver though as the space on the floppy image is tight.

As for the limited writes for CF, just use the current KNOPPIX idea of everything is in RAM and once I am done. rsync it back to the flash and pull it from the computer and go(well remember to umount to flush everything). Even with 300,000 write cycle, I can do it 10 times each day for 10 years. For the paranoid, start a cron job to do it automatically every 20 minutes so even I work on the computer for 8 hours a day, it is 24 writes, still good for 5 years use and at worse I lose 20 minutes of work(same can happen on a standard desktop).

Zentesis
08-26-2003, 08:26 PM
I newbie in Linux and I'm very interested in bootable floppy.
I read a interesting web when explain the proces for make a bootable floppy and other things. :o
The web is http://rz-obrian.rz.uni-karlsruhe.de/knoppix-usb/
In this web follow the same proces that explain the partner garyng.

But I arrived at the next point:
" Now we still need the usb modules (that aren't on the miniroot).
Mount the compressed KNOPPIX file (insmod cloop file=PATH/KNOPPIX && mount -t iso9660 /dev/cloop /cdrom) and copy the following files under /cdrom/lib/modules/$KERNELVERSION/kernel/drivers/usb/ to /mnt/modules/usb/:
ehci-hcd.o uhci.o usb-ohci.o usb-storage.o usb-uhci.o usbcore.o
Now you're finished modifying miniroot.
Umount it and gzip the file again."

I can't make the last point " Now you're finished modifying miniroot. Umount it and gzip the file again."

Anybody could explain me, point to point, how can I do? :?

HedRat
10-08-2003, 11:36 PM
No moving parts? What about a cpu and psu fan? And maybe a northbridge fab?

Still possible with an Epia motherboard and matched case with external PSU unit (like laptops). Checkout the link:

http://www.ultim8pc.co.uk/index.asp?section=products&idd=2

As far as the Mini-ITX / Epia mobo's are concerned, it's a matter of finding the fastest passively-cooled one available.

Outside of the Mini-ITX arena, there are a few full-strength passively cooled PSU's around, and you'd then have to look into heat-pipes or peltier units with external water coolers. Messy and a lot harder to spec and source - but the performance would be there.

HedRat