dd question
William A. Mahaffey III
wam at hiwaay.net
Sat Sep 26 16:05:13 UTC 2015
On 09/26/15 09:16, William A. Mahaffey III wrote:
> On 09/26/15 09:05, William A. Mahaffey III wrote:
>>
>>
>> I am preparing a USB stick for use to install FreeBSD 9.3R on 2 new
>> boxen I am bringing online. I already had the FreeBSD 9.3R img dd'ed
>> to that stick last year when I provisioned this box, but for some
>> reason, when I plugged the stick into my USB port today to copy some
>> additional files to it (scripts to be used during installs to
>> partition & slice up HDD's), I got errors in my syslog file &
>> couldn't mount the drive for the copies. No problema, I'll just re-dd
>> the image to the device & start over, all I would lose is output from
>> the previous install (this box, last year this time). However, I
>> notice the dd is proceeding *VERY* slowly:
>>
>>
>> [root at kabini1, /etc, 8:47:59am] 508 % ll /dev/da0*
>> crw-r----- 1 root operator 0xd2 Sep 26 08:29 /dev/da0
>> crw-r----- 1 root operator 0xcd Sep 26 08:29 /dev/da0a
>> [root at kabini1, /etc, 8:48:09am] 509 % ll
>> /net/q6600/home/ISOs/BSDs/FreeBSD/9.3/
>> total 1530556
>> -rw-r--r-- 1 wam users 178749440 Jul 26 2014
>> FreeBSD-9.3-RELEASE-amd64-bootonly.iso
>> -rw-r--r-- 1 wam users 671152128 Jul 26 2014
>> FreeBSD-9.3-RELEASE-amd64-disc1.iso
>> -rw-r--r-- 1 wam users 717373440 Jul 26 2014
>> FreeBSD-9.3-RELEASE-amd64-memstick.img
>> -rw------- 1 wam users 811 Jul 26 2014 checksum.MD5.txt
>> [root at kabini1, /etc, 8:48:19am] 510 % dd
>> if=/net/q6600/home/ISOs/BSDs/FreeBSD/9.3/FreeBSD-9.3-RELEASE-amd64-memstick.img
>> of=/dev/da0
>> 94834+0 records in
>> 94834+0 records out
>> 48555008 bytes transferred in 542.035379 secs (89579 bytes/sec)
>> 101599+0 records in
>> 101599+0 records out
>> 52018688 bytes transferred in 580.466607 secs (89615 bytes/sec)
>>
>> I got that output by sending the SIGINFO signal to the dd process
>> from another shell window. My question is: Why so slow (89-ish KB/s)
>> ? I have gigabit switched LAN (125 MB/s theoretical speed), & most
>> other file copies or rsyncs across the LAN go at about 1/3 - 1/2 of
>> theoretical speeds, which is AOK by me. Any ideas ? TIA & have a nice
>> weekend.
>
>
> Update: I got tired of waiting & just copied the img files over from
> the other box to do the dd in case the interaction of dd & NFS were a
> problem:
>
> [root at kabini1, /etc, 9:12:23am] 511 % cp
> /net/q6600/home/ISOs/BSDs/FreeBSD/9.3/FreeBSD-9.3-RELEASE-amd64-memstick.img
> .
> [root at kabini1, /etc, 9:12:39am] 512 % dd
> if=FreeBSD-9.3-RELEASE-amd64-memstick.img of=/dev/da0
> 3049+0 records in
> 3049+0 records out
> 1561088 bytes transferred in 17.511796 secs (89145 bytes/sec)
> ^C9584+0 records in
> 9583+0 records out
> 4906496 bytes transferred in 54.403733 secs (90187 bytes/sec)
> [root at kabini1, /etc, 9:13:51am] 513 %
> [root at kabini1, /etc, 9:13:51am] 513 %
> [root at kabini1, /etc, 9:13:52am] 513 %
> [root at kabini1, /etc, 9:13:52am] 513 % uname -a
> FreeBSD kabini1.local 9.3-RELEASE-p24 FreeBSD 9.3-RELEASE-p24 #0: Sat
> Aug 22 01:54:44 UTC 2015
> root at amd64-builder.daemonology.net:/usr/obj/usr/src/sys/GENERIC amd64
> [root at kabini1, /etc, 9:13:55am] 514 %
>
>
> Note that the cp happened pretty quick, 717-ish MiB in about 15 sec.,
> or around 45-ish MB/s, about 1/3 of max, quite acceptable to me.
> Obviously, the dd is still excruciatingly slow .... What gives ? TIA &
> have a nice weekend ....
>
Well, I got tired of waiting (again) & moved the process to my last
remaining Linux box & did the dd there. It completed OK & for grins I
inserted it back into this (FreeBSD 9.3R-p24) box. It created 2 devices:
[root at kabini1, /etc, 11:04:30am] 529 % lltr /dev/da0* ; date
crw-r----- 1 root operator 0xd1 Sep 26 11:01 /dev/da0a
crw-r----- 1 root operator 0xd0 Sep 26 11:01 /dev/da0
Sat Sep 26 11:06:37 MCDT 2015
[root at kabini1, /etc, 11:06:37am] 530 %
It used to create /dev/da0s1, but no matter, I manually mounted the da0a
partition & I can see stuff there, although it reports a bad FS size:
[root at kabini1, /etc, 11:07:53am] 530 % df -h ; w ; pstat -hms ; uname -a
; hwclock -r ; date
Filesystem Type Size Used Avail Capacity Mounted on
/dev/ada0p3 ufs 19G 11G 6.2G 65% /
devfs devfs 1.0k 1.0k 0B 100% /dev
/dev/stripe/usr_str ufs 58G 10G 43G 19% /usr
/dev/stripe/home_str ufs 3.4T 209G 3T 6% /home
procfs procfs 4.0k 4.0k 0B 100% /proc
tmpfs tmpfs 8.0G 32k 8G 0% /tmp
linprocfs linprocfs 4.0k 4.0k 0B 100%
/compat/linux/proc
fdescfs fdescfs 1.0k 1.0k 0B 100% /dev/fd
/dev/da0a ufs 682M 636M -8.8M 101% /media/sd
11:07AM up 12 days, 18:34, 7 users, load averages: 0.10, 0.28, 0.31
USER TTY FROM LOGIN@ IDLE WHAT
wam v0 - 13Sep15 12days xinit
/home/wam/.xinitrc -- /usr/local/bin/X :0 -auth /home/wam/.serverauth.1133
wam pts/5 :0 13Sep15 6days ssh -2 -X -l
wam 4256ee1
wam pts/3 :0 13Sep15 3:36 ssh -2 -X -l
wam 4256ee1
wam pts/0 :0 13Sep15 3days ssh -2 -X -l
wam 4256ee1
wam pts/2 :0 13Sep15 4days ssh -2 -X -l
wam 4256ee1
wam pts/4 :0 13Sep15 23:52 ssh -2 -X -l
wam rpib+
wam pts/1 :0 13Sep15 21 ssh -2 -X -l
wam rpib+
Device 1M-blocks Used Avail Capacity
/dev/ada0p2 4096 1.7M 4G 0%
/dev/ada1p2 4096 1.8M 4G 0%
/dev/ada2p2 4096 2M 4G 0%
/dev/ada3p2 4096 2.2M 4G 0%
Total 16384 7.6M 16G 0%
FreeBSD kabini1.local 9.3-RELEASE-p24 FreeBSD 9.3-RELEASE-p24 #0: Sat
Aug 22 01:54:44 UTC 2015
root at amd64-builder.daemonology.net:/usr/obj/usr/src/sys/GENERIC amd64
hwclock: Command not found.
Sat Sep 26 11:07:56 MCDT 2015
[root at kabini1, /etc, 11:07:56am] 531 % ll /media/sd/ ; date
total 723
-rw-r--r-- 2 root wheel 965 Jul 10 2014 .cshrc
-rw-r--r-- 2 root wheel 253 Jul 10 2014 .profile
-r--r--r-- 1 root wheel 6197 Jul 10 2014 COPYRIGHT
-r--r--r-- 1 root wheel 8553 Jul 10 2014 ERRATA.HTM
-r--r--r-- 1 root wheel 3698 Jul 10 2014 ERRATA.TXT
-r--r--r-- 1 root wheel 395727 Jul 10 2014 HARDWARE.HTM
-r--r--r-- 1 root wheel 122420 Jul 10 2014 HARDWARE.TXT
-r--r--r-- 1 root wheel 26579 Jul 10 2014 README.HTM
-r--r--r-- 1 root wheel 12965 Jul 10 2014 README.TXT
-r--r--r-- 1 root wheel 84828 Jul 10 2014 RELNOTES.HTM
-r--r--r-- 1 root wheel 24075 Jul 10 2014 RELNOTES.TXT
drwxr-xr-x 2 root wheel 1024 Jul 10 2014 bin/
drwxr-xr-x 7 root wheel 1024 Jul 10 2014 boot/
-rw-r--r-- 1 root wheel 39 Jul 10 2014 cdrom.inf
dr-xr-xr-x 2 root wheel 512 Jul 10 2014 dev/
-r--r--r-- 1 root wheel 6593 Jul 10 2014 docbook.css
drwxr-xr-x 21 root wheel 2048 Jul 10 2014 etc/
drwxr-xr-x 3 root wheel 1536 Jul 10 2014 lib/
drwxr-xr-x 3 root wheel 512 Jul 10 2014 libexec/
drwxr-xr-x 2 root wheel 512 Jul 10 2014 media/
drwxr-xr-x 2 root wheel 512 Jul 10 2014 mnt/
dr-xr-xr-x 2 root wheel 512 Jul 10 2014 proc/
drwxr-xr-x 2 root wheel 512 Jul 10 2014 rescue/
drwxr-xr-x 2 root wheel 512 Jul 10 2014 root/
drwxr-xr-x 2 root wheel 2560 Jul 10 2014 sbin/
lrwxr-xr-x 1 root wheel 11 Jul 10 2014 sys@ -> usr/src/sys
drwxrwxrwt 2 root wheel 512 Jul 10 2014 tmp/
drwxr-xr-x 15 root wheel 512 Jul 10 2014 usr/
drwxr-xr-x 24 root wheel 512 Jul 10 2014 var/
Sat Sep 26 11:07:59 MCDT 2015
[root at kabini1, /etc, 11:07:59am] 532 %
The USB drive is a 4 GB Mushkin unit. Did the naming convention for
devices change at some point in the various kernel upgrades since last
summer ? ISTR that it used to create a da0s1 device for that drive,
that's what I have in my fstab file to mount that drive manually w/o the
full mount command naming FS-type & mount point or device. Thanks for
everything so far & TIA for any more clues ....
--
William A. Mahaffey III
----------------------------------------------------------------------
"The M1 Garand is without doubt the finest implement of war
ever devised by man."
-- Gen. George S. Patton Jr.
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