On Wed, 9 Dec 2009 19:34:04 -0800 Michael Evans <mjevans1983@xxxxxxxxx> wrote: > On Wed, Dec 9, 2009 at 5:43 PM, Neil Brown <neilb@xxxxxxx> wrote: > > On Wed, 9 Dec 2009 19:29:04 +0800 > > hank peng <pengxihan@xxxxxxxxx> wrote: > > > >> I think it is better to implement this function in kernel's md layer. > >> I wonder what Neil Brown think of this? > > > > I don't think it is worth the effort. > > You probably would save some CPU time as you don't need to XOR, but as has > > been said, we are usually IO bound, not CPU bound. > > > > With the current arrangement, you can start using the array immediately - you > > don't have to wait for the initial recovery to complete. > > If you zeroed all devices at create time, you would have to wait for that to > > complete before using the array. > > > > So I see very little gain, and significant cost. > > > > NeilBrown > > > > > > When I assemble an array I tend to have checked the devices before > hand; it would not be difficult to make the final pass a zeroing pass > if I knew I could vastly speed up post-assembly performance. As I > stated, it's merely a lack of clarity in the documentation. If you would like to create a patch against the man page, I would be happy to accept it. NeilBrown -- To unsubscribe from this list: send the line "unsubscribe linux-raid" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
