Talk:Swap

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user:mike41430

The document that the "Hardware specification" page calls the "Definitive Laptop Specification", which is dated 9/13/07, says "The endurance of the NAND device is one hundred thousand erase cycles". The Swap article, with edit dates 12/23-28/07, says the "internal flash chip is only rated for 3000 writes/cell". I do not know which of these statements to believe. Did the "definitive laptop specification" become less "definitive" between 9/13 and 12/23? In particular, I would like to know the endurance rating of the flash memory in my G1G1 XO-1, ordered 11/12/07 and shipped 12/17/07. I also hope that a future release will be fixed so that it will be possible to swap on the built-in SD card slot, or use it as an extension of memory, which seems to be what was intended.
The author of that comment was someone like you, scribbling in the wiki. They were wrong. The NAND Flash used in the XO-1 has been and continues to be SLC NAND rated at 100,000 write cycles. The newer MLC NAND, and higher density SLC NAND devices both have write cycle endurances in the 5K range. But don't worry, I've been testing several for months, writing and erasing continuously to an almost full device and haven't seen problems (see NAND Testing).--Wad 05:49, 25 February 2009 (UTC)

error in parted with native partition

I am trying to do the swap-partition instructions (XO-1.0, Build 874, Fall 2011), and get the following error on the print command in Parted (v2.3):

Error: /dev/mtdblock0: unrecognised disk label

The microSD card I am using (with SD adapter) is either brand new or formatted, so it may not actually have a label, but I am worried about messing up the main system if I do mklabel. The partition list parted -l returns:

DF DU01G (sd/mmc) \\ Disk /dev/mmcblk0: 1016MB \\ Sector size (logical/physical): 512B/512B \\ Parition Table: msdos

This looks to me like the main internal drive, which thus has the linux standard label "msdos", but I thought "mtdblock0" is the internal drive. If anybody can offer guidance, please let me know and update the instructions as well.

Meanwhile, I have begrudgingly done the swap-file instead. I feel significantly less 1337 having given up for fear of breakage. SamuelRiv 20:43, 27 September 2011 (UTC)

Yes, /dev/mtdblock0 is the internal NAND FLASH, and is said to be unnecessary ... the device is removed from the latest build in 11.3.0. So an error regarding it can be ignored, I think. --Quozl 00:13, 28 September 2011 (UTC)
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