Features/Asynchronous NBD

From QEMU

Summary

Supporting asynchronous I/O in the NBD block device and qemu-nbd server makes it easier to use high-performance remote storage.

Owner

Description

The NBD block device and qemu-nbd server provide a simple base for using remote storage within QEMU. NBD can also be coupled with other features such as streaming or copy-on-read. However, the NBD implementation in QEMU is entirely synchronous, thus limiting guest performance and being hardly applicable when multiple guests use the same NBD image (for example as backing storage for QCOW or QED).

Status

Patches posted:

  • Asynchronous NBD client
  • Let tools use the QEMU main loop
  • Asynchronous NBD server

Links

  • git tree (branch nbd-trim, for the client)
  • git tree (branch split-main-loop, for the server)