JACK 0.117.0 released

JACK 0.117.0 has been released and is available here. There is one API addition, some significant implementation improvements in netjack1, and some important command line changes which will affect all JACK GUI control applications (such as qjackctl). Thanks to Torben Hohn for his continuing work on netjack1 and Florian Faber for the new sanity checking tests. Please report issues to the JACK mailing list.

• jackd now runs in realtime mode by default. the use of -R is no longer necessary. Use -L to run in non-realtime-scheduling.
• if you build JACK from source, the configure step will halt if you appear to be trying to install JACK in parallel with an existing version
• new run-time sanity checks. These are platform dependent, but on Linux JACK will check:
  • user can run with realtime priority (if JACK is going to run with RT scheduling)
  • memory locking is allowed and not unlimited
  • if using the TSC as a clock source, check that CPU frequency scaling is disabled

  If any of them are not satisfactory, jackd will print appropriate information
  to the screen, and exit with an error status. Use --no-sanity-checks or -N to disable
  these tests. There is likely
  some room for improvement in the heuristics they use, and possibly adding further runtime
  testing to ensure that JACK is likely to run correctly for the user.

• internal design of the alsa_io utilities revised, with substantial improvements. These clients
  can be configured with the same settings as you could use with jackd itself (e.g. -dhw:0 -p128 -n2),
  which previously would not have been stable. Also, the resampling quality (via libsamplerate) is
  now configurable if you need/wish to reduce CPU usage. See their respective man pages for details.

• netjack1 improvements:
  • driver command line options are more consistent with other backends and with jack_netsource,
    They are also documented on the man pages for the net backend and jack_netsource.

  • make it all work even better (you probably don't care about the details)
  • some options which allow the netjackconnect script to pierce a
    firewall and tell netjack which ports to use.

  • support for CELT 0.7.0 (note that CELT is subject to fairly
    frequent updates and if you use this for a WAN connection,
    both ends must be using the same version of CELT - it does
    not provide for any version detection or back-compatibility).

  • CELT bandwidth is now configured in Kbits per second, instead of bytes per
    period, which made the quality and bandwidth depend on periodsize.

  • the client name of jack_netsource is now "netjack"
• New JACK API function: jack_on_info_shutdown(). This is very similar to the existing jack_on_shutdown(), but if used, JACK will deliver some information about the reason for the shutdown to the client. This reflects our realization that, particularly on OS X, there are reasons why JACK might shut down that have nothing to do with client behaviour (e.g. an audio interface is unplugged or taken over by another application with new settings). See the documentation for more details.

Torben is working on web-based system for setting up WAN netjack connectivity. More news will follow on this front.