[Flashbench] Transcend Class 10 micro 8GB

[Arnd Bergmann]

arnd at klappe2:~/git/flashbench$ sudo head /sys/block/mmcblk0/device/* 2>/dev/null | grep -v ^$   
==> /sys/block/mmcblk0/device/block <==
==> /sys/block/mmcblk0/device/cid <==
744a4555534420201005402e0500b700
==> /sys/block/mmcblk0/device/csd <==
400e00325b5900003bbd7f800a400000
==> /sys/block/mmcblk0/device/date <==
07/2011
==> /sys/block/mmcblk0/device/driver <==
==> /sys/block/mmcblk0/device/erase_size <==
512
==> /sys/block/mmcblk0/device/fwrev <==
0x0
==> /sys/block/mmcblk0/device/hwrev <==
0x1
==> /sys/block/mmcblk0/device/manfid <==
0x000074
==> /sys/block/mmcblk0/device/name <==
USD  
==> /sys/block/mmcblk0/device/oemid <==
0x4a45   # ==> "JE"
==> /sys/block/mmcblk0/device/power <==
==> /sys/block/mmcblk0/device/preferred_erase_size <==
4194304
==> /sys/block/mmcblk0/device/scr <==
0235800000000000
==> /sys/block/mmcblk0/device/serial <==
0x05402e05
==> /sys/block/mmcblk0/device/subsystem <==
==> /sys/block/mmcblk0/device/type <==
SD
==> /sys/block/mmcblk0/device/uevent <==
DRIVER=mmcblk
MMC_TYPE=SD
MMC_NAME=USD  
MODALIAS=mmc:block


arnd at klappe2:~/git/flashbench$ sudo fdisk -l /dev/mmcblk0

Disk /dev/mmcblk0: 8018 MB, 8018460672 bytes

# > 7,830,528 KB


arnd at klappe2:~/git/flashbench$ sudo ./flashbench -a /dev/mmcblk0 --blocksize=1024
align 12582912  pre 391µs       on 729µs        post 624µs      diff 222µs
align 8388608   pre 391µs       on 741µs        post 641µs      diff 225µs
align 6291456   pre 413µs       on 697µs        post 671µs      diff 154µs
align 4194304   pre 359µs       on 741µs        post 649µs      diff 236µs
align 3145728   pre 408µs       on 701µs        post 654µs      diff 170µs
align 2097152   pre 405µs       on 700µs        post 655µs      diff 170µs
align 1572864   pre 402µs       on 701µs        post 660µs      diff 170µs

# --> 4 MB erase block

align 32768     pre 389µs       on 678µs        post 640µs      diff 164µs
align 24576     pre 386µs       on 670µs        post 641µs      diff 157µs
align 16384     pre 391µs       on 680µs        post 641µs      diff 164µs
align 12288     pre 535µs       on 538µs        post 496µs      diff 22.9µs
align 8192      pre 386µs       on 676µs        post 646µs      diff 160µs
align 6144      pre 460µs       on 459µs        post 422µs      diff 17.8µs
align 4096      pre 533µs       on 532µs        post 495µs      diff 17.9µs

# --> 8 KB page size

# linear access in one 4MB erase block:
arnd at klappe2:~/git/flashbench$ sudo ./flashbench  /dev/mmcblk0 --open-au --open-au-nr=1 
4MiB    12M/s   
2MiB    10.5M/s 
1MiB    10.4M/s 
512KiB  10.5M/s 
256KiB  9.93M/s 
128KiB  10.2M/s 
64KiB   10.1M/s 
32KiB   6.79M/s 
16KiB   4.44M/s 

# random access, almost as fast:
arnd at klappe2:~/git/flashbench$ sudo ./flashbench  /dev/mmcblk0 --open-au --open-au-nr=1  --random
4MiB    8.28M/s 
2MiB    8.15M/s 
1MiB    8.24M/s 
512KiB  8.12M/s 
256KiB  8.15M/s 
128KiB  8.31M/s 
64KiB   8.3M/s  
32KiB   6.71M/s 
16KiB   4.35M/s 

# across 4 erase blocks, still fast:
arnd at klappe2:~/git/flashbench$ sudo ./flashbench  /dev/mmcblk0 --open-au --open-au-nr=4  --random
4MiB    10.9M/s 
2MiB    7.1M/s  
1MiB    9.77M/s 
512KiB  9.71M/s 
256KiB  9.65M/s 
128KiB  9.45M/s 
64KiB   9.37M/s 
32KiB   6.5M/s  
16KiB   4.2M/s  

# 8 erase blocks, very slow:
arnd at klappe2:~/git/flashbench$ sudo ./flashbench  /dev/mmcblk0 --open-au --open-au-nr=8  --random
4MiB    9.39M/s 
2MiB    3.57M/s 
1MiB    2M/s    
...

# 6 erase blocks, very slow:
arnd at klappe2:~/git/flashbench$ sudo ./flashbench  /dev/mmcblk0 --open-au --open-au-nr=6  --random
4MiB    9.38M/s 
2MiB    4.47M/s 
1MiB    2M/s    
^C

# 5 erase blocks, fast:
arnd at klappe2:~/git/flashbench$ sudo ./flashbench  /dev/mmcblk0 --open-au --open-au-nr=5  --random
4MiB    8.7M/s  
2MiB    10.5M/s 
1MiB    10.4M/s 
512KiB  10.4M/s 
256KiB  10.3M/s 
128KiB  10.2M/s 
64KiB   9.99M/s 
32KiB   6.44M/s 
16KiB   4.2M/s           # page size!
8KiB    1.62M/s 
4KiB    803K/s  
2KiB	396K/s
1KiB	189K/s
512B	97B/s

# 5 erase blocks linear, same thing but slightly faster:
arnd at klappe2:~/git/flashbench$ sudo ./flashbench  /dev/mmcblk0 --open-au --open-au-nr=5   --blocksize=512
4MiB    5.98M/s 
2MiB    9.52M/s 
1MiB    9.41M/s 
512KiB  9.45M/s 
256KiB  9.35M/s 
128KiB  9.2M/s  
64KiB   9.1M/s  
32KiB   6.47M/s 
16KiB   4.1M/s  
8KiB    2.15M/s 
4KiB    1.23M/s 
2KiB    663K/s  
1KiB    340K/s  


# 6 erase blocks linear, also slow:
arnd at klappe2:~/git/flashbench$ sudo ./flashbench  /dev/mmcblk0 --open-au --open-au-nr=6   --blocksize=512
4MiB    8.79M/s 
2MiB    3.62M/s 
1MiB    1.94M/s 
^C