Re: [CentOS] slow usb hard disk performance.

Robert kerplop@sbcglobal.net wrote:

for dir in bin boot etc home initrd lib lost+found misc

opt root \ sbin selinux srv tftpboot \ usr var ; do find /$dir -depth -print0 | cpio --null -pmd $UD/$DT echo `date` Completed: /$dir >>$PF done

That's not a good benchmark. You're adding the overhead of inode/tree traversal and all sorts of other factors. You're easily cutting performance by 2-3x over.

Since USB 2.0 EHCI is capable of only 60MBps (480Mbps) theoretical, and Intel openly admits that only 30MBps is realistic, 8.8MBps is not unreasonable for this command.

Try a "raw" dd from /dev/zero, that is at least 2x your memory: dd if=/dev/zero of=(some file) bs=8M count=1000

Or consider a bonnie benchmark.