On 01/02/16 05:44, Haozhong Zhang wrote: > Hi, > > The following document describes the design of adding vNVDIMM support > for Xen. Any comments are welcome. > > Thanks, > Haozhong
Thankyou for doing this. It is a very comprehensive document, and a fantastic example for future similar situations. To start with however, I would like to clear up my confusion over the the usecases of pmem vs pblk. pblk, using indirect access, is less efficient than pmem. NVDIMMs themselves are slower (and presumably more expensive) than equivalent RAM, and presumably still has a finite number of write cycles, so I don't buy an argument suggesting that they are a plausible replacement for real RAM. I presume therefore that a system would only choose to use pblk mode in situations where the host physical address space is a limiting factor. Are there other situations which I have overlooked? Secondly, I presume that pmem vs pblk will be a firmware decision and fixed from the point of view of the Operating System? Thanks, ~Andrew _______________________________________________ Xen-devel mailing list Xen-devel@lists.xen.org http://lists.xen.org/xen-devel
