new geek toy asus eee 701

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speaking of initiation, years ago I saw the elastic band of a brief (underwear) while walking the uni campus ...

This is correct.

The technique used is that the flash memory is recycled progressively. I.e. as new writes occur, the area written "walks" around the memory.

If the drive is nearly full of data, with only a small free area being repeatedly reused, this will reduce the overall lifetime. I.e. with 90% in use and unchanging, the 51 year estimate would reduce to 5.1 years.

So... strangely counter-intuitive as it may sound, your flash drive will last LONGER, the more often you overwrite it (as in, ALL of it).

Agreed. And if a segment goes bad, you should just get a bad sector like in a regular hard drive. That will be marked as off limits to read/writes, rather than being a catastrophic failure.

I respectfully disagree with you.

Swaps are becoming smaller in comparison to overall ram size. And A lot of people dont use them at all. This xp machine, with 3 gigs of ram ram, works faster without a page file. My linux machines, with 1, 1.5 and 2 gigs or ram respectively, never seem to access their swap partitions at all. I wasnt even aware that my 2 gig machines swap wasnt mounted for for the first year.

I was under the impression that Windows XP couldn't run without a page file, regardless of the amount of installed RAM.

Yes you can. This page sums it up.
"If I have a Windows XP machine that has lots of memory, can I improve performance by removing the pagefile?"
I happen to disagree with it in regards to performance.

What you are describing is an algorithm to extend the life of a write limited device. This indeed does extend the life of the device as a whole, but as you mentioned, its not that effective if the device is at capacity. Further life could be realized if used sectors that don't get rewritten very often are swapped with sectors that are nearing failure. The list of techniques goes on and on, but all they do is extend the life of the device a little bit.

What you say would indeed work, but I have not seen any evidence that these chips actually work that way. A link would be appreciated as there isn't much on the factory website. Its also not clear exactly who is supposed to be doing all of that - the OS or the chip.



Note that their example assumes that all you do is continuously overwrite the entire device over and over. Again, note that they are talking about a 64GB device which takes 800 seconds to fully write. However, the Surf does not have 64GB, it has 2GB. It only takes 25 seconds to fully write.

So using their very optimistic best case scenario formula, 2M x 2G / 80M = 1.5 years!! !

Coincidentally, the warranty is only one year.

VERY good point.

1.5 years of continuous I/O.

Every computer deserves to rest after that. Since these have USB ports you probably can buy a new disk from which to run the OS, this is just a theory though, I have no idea.

I'm not sure what is done at present. Bear in mind that once upon a time, hard drives had no code inside them, whereas now, they are quite smart.

It certainly is no business of the OS, per se, or even the higher levels of the device driver (which are trying to make the chip appear like a "normal" HDD, in effect).

I would expect the cell management to be implemented at the lowest, hardware specific, layer of the driver. (If not in the chip itself.)

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On a bit of investigation, it would appear that the chips indeed do do their own management, these days:
http://en.wikipedia.org/wiki/Wear_levelling
http://wiki.eeeuser.com/ssd_write_limit
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I was peripherally involved in a project a decade ago: http://tfs.firshman.co.uk/ql/romdisq.htm

We did our sums... and decided that under typical usage, the limits were not a problem.

The driver did indeed do exactly as I described... in point of fact, I seem to recall that it kept an exact count of the number of writes to every cell.

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All the above certainly doesn't mean that you can't come up with a scenario that will burn out ONE CELL of a chip out in a minimal time, but that doesn't really matter.

I went to the eeuser site and I have some problems with his figures. He is claiming that the flash cells fail at 100K-200K and not 1M - 2M. Most MFG's claim the latter. The former is typical of chips made 20 years ago. Also, he is claiming that the max write speed that the eee pc is only 2-3MB/s. I admit I haven't run tests myself, but I just downloaded EEEBuntu for it and it downloaded at about 132 MB/s on another machine with a slower processor. So I'd say that 2-3MB/s seems a little low.

I got one! A 4G Asus 701, it is actually the first time I actually have a webcam.

It looks good so far, btw, regarding the SSD life, You can actually boot an operating system from an external USB flash disk! I also think you can replace the SSD, not sure though - Just saying: if the SSD died it would still not be the end of the computer's life.

Last edited by Vexcalibur on 11 Sep 2008, 11:37 pm, edited 1 time in total.

congrats Vexx!

Thanks.

BTW: http://www.tabletpcreview.com/default.asp?newsID=1263 I like this, seems like they are beginning to copy that idea of getting a cheap, small laptop and preloading it with Linux.

I haven't looked, but I think that the SSD is soldered on. I was told that the RAM is replaceable by some people and other say it isn't. I haven't looked in mine.

Mine is the 2G surf and has 2GB SSD and 512MB RAM. I wiped the original linux and installed XP on it. Then I loaded 3CX (which is a PBX VOIP switch similar to asterisk) and it seems to run OK.

In order to do that, I had to do a minimal install on it and then I had to disable page file use. The page file does two things. It prematurely burns out the SSD with continuous swapping and writing and it also wastes valuable disk space. With only XP and also using disk compression, I had 800MB to spare. When I added the 3CX software and all of its components, that number dropped to about 200MB. With only real memory and no swapper memory, the unit works pretty good. I was trying to simultaneously run a Spybot Search and Destroy scan and that was just too much of a memory drain on it and the app crashed with a "Out of memory" error.

I should point out that where you load the OS from is irrelavent as far as SSD burnout. These devices can be read an infinite number of times. The limitations is when they are written to.

Having said that, I installed Puppeee Linux to a 256MB USB stick and can boot with that when I need to. I have been using that for making Linux Tarball backups of the NTFS drive system on the Asus. In any event, I do recommend making a puppee linux USB flash drive just to have around for emergencies.

My conclusion is that while I like the 2G, I think a model with 4Gb SSD and 1Gb RAM would be a better choice for XP. The virtual memory swap file should still be disabled though. There is no reason to slow the computer down when you have plenty of real RAM.

So, it's been long since I used XP but I think it is possible to change the location of the page file, could use an external USB disk to keep the life of the SSD.