3 ms·

Also virtio-9p is slow as hell.

• throwaway7767 11y ago
  > Also virtio-9p is slow as hell. I've heard that from others, but I wonder why that is. I would expect a file-level abstraction to be faster due to less I/O roundtrips for transfers and the removal of the block-abstraction. Is it just an inefficient protocol or are there some inherent bottlenecks in a file-level sharing protocol that I'm missing? How slow is it really? Slower than NFS for example?
  • antocv 11y ago
    It was slower than NFS for me. I blame it on poor implementation, must be some bug somewhere, but I dont have the skills to find out.
  • dezgeg 11y ago
    If you want both the host and the VM to have a coherent view of the filesystem, the VM can't really do efficient caching.
    • throwaway7767 11y ago
      > If you want both the host and the VM to have a coherent view of the filesystem, the VM can't really do efficient caching. That makes sense, though it's surprising then that it's not possible to explicitly enable caching if that's the bottleneck and a coherent view from the host side is not a necessity for a given workload.