Bug#791436: Acknowledgement (base: external drive connected to usb 3.0 slows down boot process extremely)

[Michael Roediger]

Dear Maintainer,

 

I have made some interesting performance tests on my system which show clearly

the problem.

 

Here are the results:

 

root@debian:~# # The external USB drive is now connected to the USB 3.0 port
root@debian:~#
root@debian:~# # Now let us the performance to the USB drive
root@debian:~# time dd if=/dev/zero of=/media/gmr/INTENSO/hallo1.dat bs=100M count=20
20+0 Datensätze ein
20+0 Datensätze aus
2097152000 Bytes (2,1 GB) kopiert, 27,6118 s, 76,0 MB/s

real    0m27.651s
user    0m0.000s
sys    0m5.008s

 

root@debian:~# # Now let us test the performance to the internal hard disk, to the root filesystem which is ext3
root@debian:~# time dd if=/dev/zero of=/hallo1.dat bs=100M count=20
20+0 Datensätze ein
20+0 Datensätze aus
2097152000 Bytes (2,1 GB) kopiert, 1100,36 s, 1,9 MB/s

real    18m20.374s
user    0m0.000s
sys    0m8.424s

 

root@debian:~# # Now let us test the performance to the internal hard disk, to the /boot filesystem which is ext2
root@debian:~# time dd if=/dev/zero of=/boot/hallo1.dat bs=100M count=5
5+0 Datensätze ein
5+0 Datensätze aus
524288000 Bytes (524 MB) kopiert, 180,256 s, 2,9 MB/s

real    3m23.208s
user    0m0.000s
sys    0m2.224s

 

root@debian:~# # Now let us test the performance to the internal hard disk, to the /srv filesystem which is ext4
root@debian:~# # besides, the filesystem of the external USB drive is shown as vfat (df -T)
root@debian:~# time dd if=/dev/zero of=/srv/hallo1.dat bs=100M count=20
20+0 Datensätze ein
20+0 Datensätze aus
2097152000 Bytes (2,1 GB) kopiert, 592,819 s, 3,5 MB/s

real    9m52.846s
user    0m0.000s
sys    0m6.112s

 

root@debian:~# # Now I will umount the filesystem of the external USB drive, and connect it to an USB 2.1 port
root@debian:~# umount /media/gmr/INTENSO
root@debian:~# rm /hallo1.dat /boot/hallo1.dat /srv/hallo1.dat

 

root@debian:~# df -T
Dateisystem    Typ      1K-Blöcke   Benutzt Verfügbar Verw% Eingehängt auf
/dev/sda5      ext3     240177672  35336080 192634592   16% /
udev           devtmpfs     10240         0     10240    0% /dev
tmpfs          tmpfs       828708      9208    819500    2% /run
tmpfs          tmpfs      2071760       252   2071508    1% /dev/shm
tmpfs          tmpfs         5120         4      5116    1% /run/lock
tmpfs          tmpfs      2071760         0   2071760    0% /sys/fs/cgroup
/dev/sda2      ext2        960504     31124    880588    4% /boot
/dev/sda7      ext4     269452920  43236024 212506408   17% /srv
/dev/sda6      ext4     240177672  51737364 176216924   23% /home
tmpfs          tmpfs       414356         8    414348    1% /run/user/116
tmpfs          tmpfs       414356         8    414348    1% /run/user/1000
/dev/sdb1      vfat     976519104 332666496 643852608   35% /media/gmr/INTENSO

 

 

 

 

root@debian:~#
root@debian:~# # Now I will repeat all four tests again while the external USB drive is connected to USB 2.1
root@debian:~# rm /media/gmr/INTENSO/hallo1.dat
root@debian:~#
root@debian:~# time dd if=/dev/zero of=/media/gmr/INTENSO/hallo2.dat bs=100M count=20
20+0 Datensätze ein
20+0 Datensätze aus
2097152000 Bytes (2,1 GB) kopiert, 70,7906 s, 29,6 MB/s

real    1m10.800s
user    0m0.024s
sys    0m5.384s

 

root@debian:~# time dd if=/dev/zero of=/hallo2.dat bs=100M count=20
20+0 Datensätze ein
20+0 Datensätze aus
2097152000 Bytes (2,1 GB) kopiert, 31,2862 s, 67,0 MB/s

real    0m31.293s
user    0m0.000s
sys    0m5.992s

 

root@debian:~# time dd if=/dev/zero of=/boot/hallo2.dat bs=100M count=5
5+0 Datensätze ein
5+0 Datensätze aus
524288000 Bytes (524 MB) kopiert, 5,15783 s, 102 MB/s

real    0m5.216s
user    0m0.000s
sys    0m1.252s

 

root@debian:~# time dd if=/dev/zero of=/srv/hallo2.dat bs=100M count=20
20+0 Datensätze ein
20+0 Datensätze aus
2097152000 Bytes (2,1 GB) kopiert, 28,3471 s, 74,0 MB/s

real    0m28.357s
user    0m0.000s
sys    0m4.348s

 

root@debian:~# rm /media/gmr/INTENSO/hallo2.dat /hallo2.dat /boot/hallo2.dat /srv/hallo2.dat
root@debian:~#

 

 

 

root@debian:~# # Now let us umount the external USB drive again and let it disconnected at all
root@debian:~# umount /media/gmr/INTENSO
root@debian:~#

 

root@debian:~# # Now let us test the performance of the internal hard drive again
root@debian:~# time dd if=/dev/zero of=/hallo3.dat bs=100M count=20
20+0 Datensätze ein
20+0 Datensätze aus
2097152000 Bytes (2,1 GB) kopiert, 27,36 s, 76,7 MB/s

real    0m27.370s
user    0m0.000s
sys    0m6.080s

 

root@debian:~# time dd if=/dev/zero of=/boot/hallo3.dat bs=100M count=5
5+0 Datensätze ein
5+0 Datensätze aus
524288000 Bytes (524 MB) kopiert, 4,92683 s, 106 MB/s

real    0m4.934s
user    0m0.000s
sys    0m1.268s

 

root@debian:~# time dd if=/dev/zero of=/srv/hallo3.dat bs=100M count=20
20+0 Datensätze ein
20+0 Datensätze aus
2097152000 Bytes (2,1 GB) kopiert, 28,3315 s, 74,0 MB/s

real    0m28.339s
user    0m0.000s
sys    0m4.376s

 

root@debian:~# rm /hallo3.dat /boot/hallo3.dat /srv/hallo3.dat

 

Hints:

"Datensätze ein" means records in

"Datensätze aus" means records out

"kopiert" means copied

 

Kind regards,

Michael

 

-- To UNSUBSCRIBE, email to debian-bugs-dist-requ...@lists.debian.org with a subject of "unsubscribe". Trouble? Contact listmas...@lists.debian.org