High read write IO on Fresh noobs Raspbian install

[pegasus1001]

Hi guys,

Just got my Rpi2 and first thing I did was to boot up NOOBs and setup Raspbian on the SD card. Then, I followed the Extended Instructions in viewtopic.php?f=29&t=44177 to transfer my Raspbian setup from SD to USB (sda) so that I run off USB instead of SD.

It was booting into USB when it is all done and was running fine. However, since then, the USB's built in LED has been flashing constantly leading me to think that something is reading/writing into the USB. I done a quick iotop and it didn't show anything being written into except for the occasional jdb2/sda1-8 (which I found out to be the journaling for ext4)... left it overnight and it is still flashing...

Any ideas? I don't want prematurely kill a USB due to the high IO.

PS: This is the latest version of NOOBS that I got off the internet. SD card is from Rpi (Class 10). USB stick is a Toshiba Transmemory 8GB. Raspbian is a fresh install from NOOBS and have not installed anything else besides gdisk and iotop

[pegasus1001]

Just swapped back to SD card for the fs, noticed that the green LED have this small flicker constantly. It doesn't seem obvious unless you look very closely. Is this normal?

Attached iotop with the USB light flickering nonstop

iotop

iotop.png (43.88 KiB) Viewed 1137 times

pi@raspberrypi ~ $ df -h
Filesystem Size Used Avail Use% Mounted on
rootfs 7.0G 2.5G 4.2G 37% /
/dev/root 7.0G 2.5G 4.2G 37% /
devtmpfs 460M 0 460M 0% /dev
tmpfs 93M 268K 93M 1% /run
tmpfs 5.0M 0 5.0M 0% /run/lock
tmpfs 186M 0 186M 0% /run/shm
/dev/mmcblk0p5 60M 19M 42M 32% /boot


pi@raspberrypi ~ $ mount
/dev/root on / type ext4 (rw,noatime,data=ordered)
devtmpfs on /dev type devtmpfs (rw,relatime,size=470416k,nr_inodes=117604,mode=755)
tmpfs on /run type tmpfs (rw,nosuid,noexec,relatime,size=94944k,mode=755)
tmpfs on /run/lock type tmpfs (rw,nosuid,nodev,noexec,relatime,size=5120k)
proc on /proc type proc (rw,nosuid,nodev,noexec,relatime)
sysfs on /sys type sysfs (rw,nosuid,nodev,noexec,relatime)
tmpfs on /run/shm type tmpfs (rw,nosuid,nodev,noexec,relatime,size=189880k)
devpts on /dev/pts type devpts (rw,nosuid,noexec,relatime,gid=5,mode=620,ptmxmode=000)
/dev/mmcblk0p5 on /boot type vfat (rw,relatime,fmask=0022,dmask=0022,codepage=437,iocharset=ascii,shortname=mixed,errors=remount-ro)


Ran dstat and this is what I've got. All the while, the USB is flickering. Seems weird that on the second minute on, it is 0 rw
pi@raspberrypi ~ $ dstat -tdD total,sda 60
----system---- -dsk/total----dsk/sda--
time | read writ: read writ
04-06 20:59:06| 149k 125k: 146k 125k
04-06 21:00:06| 0 7168B: 0 7168B
04-06 21:01:06| 0 0 : 0 0
04-06 21:02:06| 0 0 : 0 0

[ktb]

http://www.commandlinefu.com/commands/v ... -a-journal

[pegasus1001]

http://www.commandlinefu.com/commands/v ... -a-journal

Thanks for the reply ktb. I've disabled journaling and the problem is still there.

Did this
sudo -i
echo 1 > /proc/sys/vm/block_dump # Start logging
# Wait 1 minute
echo 0 > /proc/sys/vm/block_dump # Stop logging
exit

and kern.log shows this... I'm thinking that the kworker is writing to disk constantly that's why journaling was running constantly.

Jun 4 23:01:36 raspberrypi kernel: [ 154.408508] rs:main Q:Reg(2053): dirtied inode 157513 (debug) on sda1
Jun 4 23:01:36 raspberrypi kernel: [ 154.408544] rs:main Q:Reg(2053): dirtied inode 157513 (debug) on sda1
Jun 4 23:01:36 raspberrypi kernel: [ 154.408567] rs:main Q:Reg(2053): dirtied inode 157513 (debug) on sda1
Jun 4 23:02:06 raspberrypi kernel: [ 184.457882] kworker/u8:2(54): WRITE block 4207904 on sda1 (8 sectors)
Jun 4 23:02:06 raspberrypi kernel: [ 184.457957] kworker/u8:2(54): WRITE block 4207912 on sda1 (8 sectors)
Jun 4 23:02:06 raspberrypi kernel: [ 184.457994] kworker/u8:2(54): WRITE block 4902896 on sda1 (8 sectors)
Jun 4 23:02:06 raspberrypi kernel: [ 184.458040] kworker/u8:2(54): WRITE block 8 on sda1 (8 sectors)
Jun 4 23:02:06 raspberrypi kernel: [ 184.458076] kworker/u8:2(54): WRITE block 4194312 on sda1 (8 sectors)
Jun 4 23:02:06 raspberrypi kernel: [ 184.458481] kworker/u8:2(54): WRITE block 90432 on sda1 (16 sectors)
Jun 4 23:02:06 raspberrypi kernel: [ 184.458567] kworker/u8:2(54): WRITE block 89920 on sda1 (8 sectors)
Jun 4 23:02:06 raspberrypi kernel: [ 184.458626] kworker/u8:2(54): WRITE block 4456472 on sda1 (8 sectors)