Harley: > Old 36GB drives: > > | # time mkfile -v 1g zeros-1g > | zeros-1g 1073741824 bytes > | > | real 2m31.991s > | user 0m0.007s > | sys 0m0.923s > > Newer 300GB drives: > > | # time mkfile -v 1g zeros-1g > | zeros-1g 1073741824 bytes > | > | real 0m8.425s > | user 0m0.010s > | sys 0m1.809s
This is a pretty dramatic difference. What type of drives were your old 36g drives? > I am wondering if there is something other than capacity > and seek time which has changed between the drives. Would a > different scsi command set or features have this dramatic a > difference? I'm hardly the authority on hardware, but there are a couple of possibilties. Your newer drives may have a write cache. It's also quite likely that the newer drives have a faster speed of rotation and seek time. If you subtract the usr + sys time from the real time in these measurements, I suspect the result is the amount of time you were actually waiting for the I/O to finish. In the first case, you spent 99% of your total time waiting for stuff to happen, whereas in the second case it was only ~86% of your overall time. -j _______________________________________________ zfs-discuss mailing list zfs-discuss@opensolaris.org http://mail.opensolaris.org/mailman/listinfo/zfs-discuss
