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From IGEP - ISEE Wiki
→#001 : Basic read/write operation
$ time dd if=/dev/zero of=/dev/mmcblk0
The time used for the calculations rate transfer was the time reported by dd.
Results:
|-
! Test (SD 2GB)
! 2.6.3335.y9 (OMAP35x)
|-
| read
| 13.7 MB/s (2m 33s23.55s)
|-
| write
| 3.2 MB/s (10m 13s13.44s)
|}
'''Notes:'''
src: http://jozz.no-ip.org/wiki/host/tips_and_trix
Says performance can be improved by letting more memory be used as buffers and delaying writeback doing
echo 1500 > /proc/sys/vm/dirty_writeback_centisecs
echo 50 > /proc/sys/vm/dirty_ratio
echo 50 > /proc/sys/vm/dirty_background_ratio
The results are:
# time dd if=/dev/mmcblk0 of=/dev/null
3842048+0 records in
3842048+0 records out
1967128576 bytes (2.0 GB) copied, 148.344 seconds, 13.3 MB/s
real 2m 28.35s
user 0m 5.67s
sys 0m 19.66s
# time dd if=/dev/zero of=/dev/mmcblk0
dd: writing to `/dev/mmcblk0': No space left on device
3842049+0 records in
3842048+0 records out
1967128576 bytes (2.0 GB) copied, 578.973 seconds, 3.4 MB/s
Command exited with non-zero status 1
real 9m 39.00s
user 0m 3.64s
sys 0m 39.77s
Conclusion: No big difference with this test.
= OneNAND =
