[virt-tools-list] ANNOUNCE: libnbd 0.9.8 - prerelease of high performance NBD client library

[Richard W.M. Jones]

I'm pleased to announce a new high performance Network Block Device
(NBD) client library called libnbd.  It's written in C and there are
also bindings available for Python, OCaml and (soon) Rust.

0.9.8 is the third pre-release before the stable 1.0 version where we
freeze the API, so feedback on API-related issues is very welcome now.

Download:       http://download.libguestfs.org/libnbd/
Documentation:  https://github.com/libguestfs/libnbd/blob/master/docs/libnbd.pod
Fedora package: https://koji.fedoraproject.org/koji/packageinfo?packageID=28807
Debian package: https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=933223
Git repo:       https://github.com/libguestfs/libnbd
Mailing list:   libguestfs at redhat.com (no subscription required)

Here are some of the things you can do with this library ...

Connect to an NBD server and grab the first sector of the disk:
https://github.com/libguestfs/libnbd/blob/a5f8fd2f0f48e9cf2487e23750b55f67b166014f/examples/simple-fetch-first-sector.c#L14

High performance multi-threaded reads and writes, with multiple
connections and multiple commands in flight on each connection:
https://github.com/libguestfs/libnbd/blob/master/examples/threaded-reads-and-writes.c

Integrate with glib main loop:
https://github.com/libguestfs/libnbd/blob/master/examples/glib-main-loop.c

Connect to an NBD server from an interactive shell:

  $ nbdkit -f linuxdisk . &
  $ nbdsh --connect nbd://localhost

  Welcome to nbdsh, the shell for interacting with
  Network Block Device (NBD) servers.

  nbd> h.get_size()
  716266496
  nbd> buf = h.pread (512, 0)
  nbd> print ("%r" % buf)
  [prints the first sector]

Use ‘fio’ to benchmark an NBD server:

  $ nbdkit -U - memory size=256M \
        --run 'export unixsocket ; fio examples/nbd.fio '

Rich.

-- 
Richard Jones, Virtualization Group, Red Hat http://people.redhat.com/~rjones
Read my programming and virtualization blog: http://rwmj.wordpress.com
libguestfs lets you edit virtual machines.  Supports shell scripting,
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