Yep, I have been reading that code. I think libaio would be more efficient when using faster backing devices but it's probably not a problem due to how MD is structured. If you have one vnode/md for each physical disk it should result in good IO performance. I intend on testing sheepdog with some big 36 drive machines soon to prove that theory though, try get feel for how well MD scales. On Thu, May 23, 2013 at 12:59 AM, Liu Yuan <namei.unix at gmail.com> wrote: > On 05/23/2013 03:38 PM, Joseph Glanville wrote: >> One of the drawbacks of dropping O_DIRECT support is that it would be >> hard to integrate a Linux libaio native IO engine. > > We use threads poll instead of one thead + linux native aio, so this is > not a problem at least for now. > > Thanks, > Yuan |