dd is so slow on my SCSI disc

Sebastian Pahlke sp.ibm at gmx.de
Mon Aug 22 20:13:36 GMT 2005

Hi all,

I'm trying to "clean" a disc before selling them:

dd if=/dev/zero of=/dev/da0

Do I make something wrong because the transfer rate is only 60932
bytes/sec??? These are 60 kbytes/sec, slower than my internet connection!!!

I tried to increase the block size, with bs=32768 I get 3416071 bytes/sec.
But this is still very poor. The system is a PIII 800MHz and a SCSI-3 disc
in single user mode booted from FreeBSD release 5.4 live-cd.

Any ideas how to analyze this? Thanks in advance!


Sebastian Pahlke 

More information about the freebsd-questions mailing list