Hi Warner, On Friday 09 January 2009 17:50:27 M. Warner Losh wrote: > I just copied a disk using dump + restore. I noticed something > through the whole run of this 500GB operation: > > L(q) ops/s r/s kBps ms/r w/s kBps ms/w %busy Name > 3 231 231 14754 9.5 0 0 0.0 97.5| da1s1a > 0 39 0 0 0.0 39 4982 10.0 38.7| da2s1a > > The read kBps was 3x the write kBps. While the dump is going through > the raw device, and the restore is going through the file system, I > can't imagine why we'd have such a huge difference that would be utter > consistent for the whole 15 hour run. > > Any ideas what gives? I observed this with 16MB cache and with 32MB > cache, fwiw.
I've noticed this too. Last week I upgraded a laptop harddisk and used dump + restore to copy files from the original harddisk (attached to the laptop using a USB bracket). During the entire copy process I also saw about a 3x difference. -- Daan _______________________________________________ freebsd-hackers@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-hackers To unsubscribe, send any mail to "freebsd-hackers-unsubscr...@freebsd.org"
