Speed of NAND flash vs. SD card (Was: Ain't it funny..)

[Rask Ingemann Lambertsen]

On Tue, May 05, 2009 at 07:12:25AM -0600, Angus Ainslie wrote:

> You could always use the .tar.gz on an sd card ( It boots way faster
> that way anyway :)

   NAND flash ought to be a lot faster than Glamo's MMC interface. Where is
the bug? FWIW, I tried a simple hdparm run on NOR flash, NAND flash and SD
card:

root at debian-gta02:~# hdparm --direct -t /dev/mtdblock0	# NOR flash

/dev/mtdblock0:
 Timing O_DIRECT disk reads:    2 MB in  1.24 seconds =   1.61 MB/sec

root at debian-gta02:~# hdparm --direct -t /dev/mtdblock3	# NAND flash

/dev/mtdblock3:
 Timing O_DIRECT disk reads:    8 MB in  2.89 seconds =   2.77 MB/sec

root at debian-gta02:~# hdparm --direct -t /dev/mmcblk0	# Glamo MMC

/dev/mmcblk0:
 Timing O_DIRECT disk reads:    8 MB in  3.46 seconds =   2.31 MB/sec

-- 
Rask Ingemann Lambertsen
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