Hello Matthew, Tuesday, May 8, 2007, 1:04:56 AM, you wrote:
MA> Pawel Jakub Dawidek wrote: >> This is what I see on Solaris (hole is 4GB): >> >> # /usr/bin/time dd if=/ufs/hole of=/dev/null bs=128k >> real 23.7 >> # /usr/bin/time dd if=/zfs/hole of=/dev/null bs=128k >> real 21.2 >> >> # /usr/bin/time dd if=/ufs/hole of=/dev/null bs=4k >> real 31.4 >> # /usr/bin/time dd if=/zfs/hole of=/dev/null bs=4k >> real 7:32.2 MA> This is probably because the time to execute this on ZFS is dominated by MA> per-systemcall costs, rather than per-byte costs. You are doing 32x more MA> system calls with the 4k blocksize, and it is taking 20x longer. MA> That said, I could be wrong, and yowtch, that's much slower than I'd like! But 4k for UFS took him 31s while 4k for ZFS took him 14x more time! In both cases the same number of syscalls were executed. -- Best regards, Robert mailto:[EMAIL PROTECTED] http://milek.blogspot.com _______________________________________________ zfs-discuss mailing list zfs-discuss@opensolaris.org http://mail.opensolaris.org/mailman/listinfo/zfs-discuss
