Russell Coker posted on Wed, 25 Nov 2015 18:20:25 +1100 as excerpted: > On Sun, 15 Nov 2015 03:01:57 PM Duncan wrote: >> That looks to me like native drive limitations. >> >> Due to the fact that a modern hard drive spins at the same speed no >> matter where the read/write head is located, when it's reading/writing >> to the first part of the drive -- the outside -- much more linear drive >> distance will pass under the read/write heads in say a tenth of a >> second than will be the case as the last part of the drive is filled -- >> the inside -- and throughput will be much higher at the first of the >> drive. > > http://www.coker.com.au/bonnie++/zcav/results.html > > The above page has the results of my ZCAV benchmark (part of the > Bonnie++ suite) which shows this. You can safely tun ZCAV in read mode > on a device that's got a filesystem on it so it's not too late to test > these things.
Thanks. Those graphs are pretty clear. As you, I'd have thought there'd be far fewer zones (3-4) than it turns out there are (8ish). -- Duncan - List replies preferred. No HTML msgs. "Every nonfree program has a lord, a master -- and if you use the program, he is your master." Richard Stallman -- To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
