まとめ

Sandisk Extreme microSDHC 16GB Read:74.34MB/s / Write:53.58MB/s (Win7_64 + CrystalDiskBenchにて))

RPi3

Overlay config                      core_freq   turbo   overclock_50    WRITE        READ        HDPARM
                                       400        0      50.000 MHz   20.85 MB/s   21.91 MB/s   22.15 MB/s
dtoverlay=sdtweak,overclock_50=100     400        0     100.000 MHz   22.89 MB/s   34.67 MB/s   34.58 MB/s

RPi2にて

Overlay config                      core_freq   turbo   overclock_50    WRITE        READ        HDPARM
                                       250        0      50.000 MHz   20.55 MB/s   21.71 MB/s   21.93 MB/s
dtoverlay=sdhost,overclock_50=63       250        0      62.500 MHz   22.64 MB/s   26.75 MB/s   27.09 MB/s
dtoverlay=sdhost,overclock_50=84       250        0      83.333 MHz   22.98 MB/s   34.88 MB/s   35.41 MB/s

ASUS_TinkerBoard(参考)

Overlay config                      core_freq   turbo   mmc0:BusSpeed   WRITE        READ        HDPARM
                                       ???        ?     148.500 MHz   45.88 MB/s   50.97 MB/s   43.67 MB/s

概要

らずぱいでの microSDのベンチマークでも... と、ぐーぐる先生にお尋ねしてたら、らずぱいで、SDのクロックアップできるよ、という記事を発見。
> How to overclock the microSD card reader on a Raspberry Pi 3
/boot/config.txtを書き換えるだけ。
だが、正常に動作しないのもある。(起動できても、計測中におかしくなるのもあった)
core_freqを整数で割ったクロックをSDに提供できる、っぽい。
- RPi3 : core_freq=400なので、overclock_50= 100/80/67/58/50あたり
- RPi0,1,2: core_freq=250なので、overclock_50= 100/84/63/50あたり
RPi2/3とも、READで1.6倍くらい(21->34MB/s)、Writeで 1.1倍(21->23MB/s)速くなった。(うちにある一番速いmicroSDを使って、ベンチマークテストの上では..)

環境

Raspberry Pi 3 クーリングファン付
Raspberry Pi 2 ヒートシンク付 (SanDisk Extremeのみ計測)
Raspbian: 2017-03-02-raspbian-jessie-lite.img (アップデート無し)
1. sshとwpa_supplicant.conf(Wifi設定)をbootパーティションへ
2. 起動直後: sudo apt-get update && sudo apt-get install -y hdparm curl build-essential

config.txtで、sdをクロックアップ

sudo bash -c 'printf "dtoverlay=sdhost,overclock_50=100\n" >> /boot/config.txt'
Wifiがおかしいとき(??)、

sudo bash -c 'printf "dtoverlay=sdtweak,overclock_50=100\n" >> /boot/config.txt'

overclocking~~~というのが出てくる

pi@raspberrypi:~ $ dmesg | grep mmc0
[    0.879166] mmc0: sdhost-bcm2835 loaded - DMA enabled (>1)
[    0.936907] mmc0: host does not support reading read-only switch, assuming write-enable
[    0.983164] mmc0: overclocking to 100000000Hz
[    0.985417] mmc0: new high speed SDHC card at address 0007
[    0.988083] mmcblk0: mmc0:0007 SD8GB 7.42 GiB
pi@raspberrypi:~ $

テスト手順

Windows7 64bitで、CrystalDsiakMarkにて、microSDの速度を測る
- USB3.0カードリーダ IOGEAR GFR304SD使用

curl http://www.nmacleod.com/public/sdbench.sh | sudo bash

sdbench.sh

...
HDCMD="hdparm -t --direct /dev/mmcblk0 | grep Timing"
WRCMD="rm -f ${FILENM} && sync && dd if=/dev/zero of=${FILENM} bs=1M count=${DATAMB} conv=fsync 2>&1 | grep -v records"
RDCMD="echo 3 > /proc/sys/vm/drop_caches && sync && dd if=${FILENM} of=/dev/null bs=1M 2>&1 | grep -v records"
...

結果

Kingston Digital 8 GB microSDHC Class 10 UHS-1 Memory Card 30MB/s with Adapter (SDC10/8GB)

RPi3

Overlay config                      core_freq   turbo   overclock_50    WRITE        READ        HDPARM
                                       400        0      50.000 MHz    9.24 MB/s   18.73 MB/s   21.10 MB/s
dtoverlay=sdtweak,overclock_50=100     400        0     100.000 MHz    8.17 MB/s   19.00 MB/s   21.07 MB/s

PiZEROのセットを買ったときついてきたmicroSD (Ultimate 3.0 70MB/s 8GB とかいてある)

リードは 70MB/s超えてるんだけどね...

RPi3

Overlay config                      core_freq   turbo   overclock_50    WRITE        READ        HDPARM
                                       400        0      50.000 MHz    7.05 MB/s   20.39 MB/s   21.10 MB/s
dtoverlay=sdtweak,overclock_50=100     400        0     100.000 MHz    7.18 MB/s   30.39 MB/s   28.81 MB/s

Sandisk Extreme MICROSDHC 16GB 90MB/S Flash Memory Card(たぶん..)

RPi3

Overlay config                      core_freq   turbo   overclock_50    WRITE        READ        HDPARM
                                       400        0      50.000 MHz   20.85 MB/s   21.91 MB/s   22.15 MB/s
dtoverlay=sdtweak,overclock_50=100     400        0     100.000 MHz   22.89 MB/s   34.67 MB/s   34.58 MB/s

RPi2にて

Overlay config                      core_freq   turbo   overclock_50    WRITE        READ        HDPARM
                                       250        0      50.000 MHz   20.55 MB/s   21.71 MB/s   21.93 MB/s
dtoverlay=sdhost,overclock_50=63       250        0      62.500 MHz   22.64 MB/s   26.75 MB/s   27.09 MB/s
dtoverlay=sdhost,overclock_50=84       250        0      83.333 MHz   22.98 MB/s   34.88 MB/s   35.41 MB/s

Samsung Electronics 32GB EVO Micro SDHC UHS-I Upto 48MB/s Class 10 Memory Card (MB-MP32D)

RPi3

Overlay config                      core_freq   turbo   overclock_50    WRITE        READ        HDPARM
                                       400        0      50.000 MHz   18.16 MB/s   21.56 MB/s   21.76 MB/s
dtoverlay=sdtweak,overclock_50=80      400        0      80.000 MHz   18.98 MB/s   23.35 MB/s   24.47 MB/s

100MHz設定では、カードエラーがでて正常動作しなかった。

その他

追記2017-0411:　RPi3 + SanDiskExtreme16GBにて、overclock_50=134=> 133.33MHzは、だめだった(133,125とトライして、100MHzまでおちる)

overclock_50=134...はだめだった

pi@raspberrypi:~ $ grep overclock_50 /boot/config.txt 
dtoverlay=sdtweak,overclock_50=134
pi@raspberrypi:~ $ dmesg | grep mmc0
[    0.878893] mmc0: sdhost-bcm2835 loaded - DMA enabled (>1)
[    0.956086] mmc0: host does not support reading read-only switch, assuming write-enable
[    0.985908] mmc0: overclocking to 133333333Hz
[    0.988111] mmc0: unexpected command 55 error
[    0.990268] mmc0: reducing overclock due to errors
[    0.992463] mmc0: overclocking to 125000000Hz
[    0.994536] mmc0: unexpected command 55 error
[    0.996580] mmc0: reducing overclock due to errors
[    0.998689] mmc0: overclocking to 100000000Hz
[    1.002811] mmc0: new high speed SDHC card at address aaaa
[    1.005335] mmcblk0: mmc0:aaaa SE16G 14.8 GiB
pi@raspberrypi:~ $

おまけ: ASUS Tinker Board にて : 20170330-tinker-board-linaro-jessie-alip-v1.6.img使用

Overlay config                      core_freq   turbo   overclock_50    WRITE        READ        HDPARM
                                       0        0                   45.88 MB/s   50.97 MB/s   43.67 MB/s
----
Linux linaro-alip 4.4.16 #1 SMP Thu Mar 30 22:22:19 CST 2017 armv7l GNU/Linux   
[    2.998529] mmc_host mmc0: Bus speed (slot 0) = 148500000Hz (slot req 150000000Hz, actual 148500000HZ div = 0)

らずぱいと同じスクリプトを実行したので、それっぽいとこでエラーでてるが、測定値はOK、かと。

sudo apt-get update && sudo apt-get install -y hdparm curl build-essential
curl http://www.nmacleod.com/public/sdbench.sh | sudo bash
dmesg | grep mmc0
uname -a
...
...
...
grep: /boot/config.txt: No such file or directory
bash: line 46: vcgencmd: command not found
bash: line 47: vcgencmd: command not found
bash: line 48: vcgencmd: command not found
cat: /sys/devices/system/cpu/cpufreq/ondemand/io_is_busy: No such file or directory
CONFIG: 
CLOCK : 
CORE  :  MHz, turbo=
DATA  : 512 MB, /root/test.dat

HDPARM:
======
 Timing O_DIRECT disk reads: 128 MB in  3.04 seconds =  42.05 MB/sec
 Timing O_DIRECT disk reads: 132 MB in  3.02 seconds =  43.70 MB/sec
 Timing O_DIRECT disk reads: 136 MB in  3.01 seconds =  45.15 MB/sec

WRITE:
=====
536870912 bytes (537 MB) copied, 11.2337 s, 47.8 MB/s
536870912 bytes (537 MB) copied, 11.0605 s, 48.5 MB/s
536870912 bytes (537 MB) copied, 11.1862 s, 48.0 MB/s

READ:
====
536870912 bytes (537 MB) copied, 10.2028 s, 52.6 MB/s
536870912 bytes (537 MB) copied, 11.2799 s, 47.6 MB/s
536870912 bytes (537 MB) copied, 8.92718 s, 60.1 MB/s

RESULT (AVG):
============
Overlay config                      core_freq   turbo   overclock_50    WRITE        READ        HDPARM
                                       0        0                   45.88 MB/s   50.97 MB/s   43.67 MB/s
linaro@linaro-alip:~$ dmesg | grep mmc0
[    2.897976] mmc_host mmc0: Bus speed (slot 0) = 400000Hz (slot req 400000Hz, actual 400000HZ div = 0)
[    2.998529] mmc_host mmc0: Bus speed (slot 0) = 148500000Hz (slot req 150000000Hz, actual 148500000HZ div = 0)
[    3.689367] mmc0: new ultra high speed SDR104 SDHC card at address aaaa
[    3.692071] mmcblk0: mmc0:aaaa SE16G 14.8 GiB 
linaro@linaro-alip:~$ uname -a
Linux linaro-alip 4.4.16 #1 SMP Thu Mar 30 22:22:19 CST 2017 armv7l GNU/Linux
linaro@linaro-alip:~$