Tim wrote: > On Sun, Jan 18, 2009 at 2:43 PM, Richard Elling <richard.ell...@sun.com > <mailto:richard.ell...@sun.com>> wrote: > > comment at the bottom... > DIY. Personally, I'd be more upset if ZFS reserved any sectors > for "some potential swap I might want to do later, but may never > need to do." If you want to reserve some space for swappage, DIY. > > As others have noted, this is not a problem for systems vendors > because we try, and usually succeed, at ensuring that our multiple > sources of disk drives are compatible such that we can swap one > for another. > -- richard > > > > And again I call BS. I've pulled drives out of a USP-V, Clariion, DMX, > and FAS3040. Every single one had drives of slightly differing sizes. > Every single one is right-sized at format time.
It is naive to think that different storage array vendors would care about people trying to use another array vendors disks in their arrays. In fact, you should get a flat, impersonal, "not supported" response. What vendors can do, is make sure that if you get a disk which is supported in a platform and replace it with another disk which is also supported, and the same size, then it will just work. In order for this method to succeed, a least, common size is used. > Hell, here's a filer I have sitting in a lab right now: > > RAID Disk Device HA SHELF BAY CHAN Pool Type RPM Used > (MB/blks) Phys (MB/blks) > --------- ------ ------------- ---- ---- ---- ----- > -------------- -------------- > dparity 0b.32 0b 2 0 FC:B - FCAL 10000 > 68000/139264000 68444/140174232 > parity 0b.33 0b 2 1 FC:B - FCAL 10000 > 68000/139264000 68444/140174232 > data 0b.34 0b 2 2 FC:B - FCAL 10000 > 68000/139264000 68552/140395088 > > Notice line's 2 and 3 are different physical block size, and those are > BOTH seagate cheetah's, just different generation. So, it gets short > stroked to 68000 from 68552 or 68444. > > And NO, the re-branded USP-V's Sun sell's don't do anything any > differently, so stop lying, it's getting old. Vendors can change the default label, which is how it is implemented. For example, if we source XYZ-GByte disks from two different vendors intended for the same platform, then we will ensure that the number of available sectors is the same, otherwise the FRU costs would be very high. No conspiracy here... just good planning. > If you're so concerned with the storage *lying* or *hiding* space, I > assume you're leading the charge at Sun to properly advertise drive > sizes, right? Because the 1TB drive I can buy from Sun today is in no > way, shape, or form able to store 1TB of data. You use the same *fuzzy > math* the rest of the industry does. There is no fuzzy math. Disk vendors size by base 10. They explicitly state this in their product documentation, as business law would expect. http://en.wikipedia.org/wiki/Mebibyte -- richard _______________________________________________ zfs-discuss mailing list zfs-discuss@opensolaris.org http://mail.opensolaris.org/mailman/listinfo/zfs-discuss
