expected write speed on microSD

[Harald Koenig]

On Sep 19, Nicolas Chauvat wrote:

> On Fri, Sep 19, 2008 at 12:38:49PM +0000, Jan R wrote:
> > Assuming the file system on the card is ext2, check that it is not 
> > mounted with the "sync" option (automount usually mounts it that way).
> > I had the same speed problem, and it magically vanished after remounting 
> > it without synchronous I/O.
> 
> $ mount -o remount,async /dev/mmcblk0p2
> 
> solved my problem. Thanks !

gaaa!  this also affects my recent performace numbers :-(

I used direct read/write to /dev/mmcblk0p3 but this partition 
still was sync-mounted!  after unmounting I get

~1.1 Mbyte/sec read:

    1088 K     0.9355    0.9355     1190935   1120880
    2112 K     1.8744    0.9389     1153796   1116793
    3136 K     2.8341    0.9597     1133093   1092654
    4160 K     3.7621    0.9281     1132293   1129850
    5184 K     4.7092    0.9470     1127252   1107226

~1.4 Mbyte/sec write:

   78912 K    52.9782    0.2834     1525267   3699933
   79936 K    57.8466    4.8685     1415025    215381
   80960 K    58.0113    0.1647     1429083   6367664
   81984 K    58.2917    0.2804     1440198   3739745
   83008 K    58.6144    0.3227     1450158   3249453


but it's still worse than in August, and enable/disable "sd_idleclk"
doesn'tseem to make any difference...

Harald
-- 
"I hope to die                                      ___       _____
before I *have* to use Microsoft Word.",           0--,|    /OOOOOOO\
Donald E. Knuth, 02-Oct-2001 in Tuebingen.        <_/  /  /OOOOOOOOOOO\
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                                                      \ OOOOOOOOOOOOOOOOO|//
                                                       \/\/\/\/\/\/\/\/\/
Harald Koenig                                           //  /     \\  \
koenig at tat.physik.uni-tuebingen.de                     ^^^^^       ^^^^^