dd backup unbelievably slow on SATA laptop

Kevin Kempter kevin at kevinkempterllc.com
Thu Jan 4 16:14:38 UTC 2007


Hi List;

I have FC5 on an IBM Thinkpad Z60m with 2G of RAM and a 100G SATA HD.  I also 
have a removeable CD/DVD drive and I can insert a HD adapter into 
the "ultrabay" which adds a second HD attached to the main bus (as the CD/DVD 
would be).

I inserted the second 100G ATA HD into the ultrabay and booted into single 
user mode. The second HD shows up as /dev/hdc my main HD shows up 
as /dev/sda.  (Note if I boot with hdc=noprobe into single user mode then the 
system is not aware of the root user)

I run this:
dd if=/dev/sda of=/dev/hdc bs=64K & 
pid=$!

Note: I've tried the same with bs=128K, bs=1M, bs=256K and with no bs tag at 
all with the same results

Then I check the progress from time to time with this:
kill -USR1 $pid

I find that my avg speed in 1.7m/sec which leads to a full backup time of 
around 16-17 hours.

Before the deal with M$ I used to run SuSE 10 and was able to do a dd on the 
same laptop inside of 4 hours.  

Any help would be much appreciated....

Thanks in advance




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