New firewire stack makes more FFADO XRUNs than old firewire stack.
Affects | Status | Importance | Assigned to | Milestone | |
---|---|---|---|---|---|
libffado (Ubuntu) |
Won't Fix
|
Undecided
|
Unassigned |
Bug Description
I have a firewire audio device, M-Audio Firewire Solo. It works fine in Lucid but not so good in Marveric because of much FFADO XRUNs in jackd2.
My IEEE 1394 chipset is below,
FireWire (IEEE 1394): Ricoh Co Ltd R5C832 IEEE 1394 Controller (rev 04)
$ dpkg -l | grep ffado
ii ffado-dbus-server 2.0.1+svn1856-
ii ffado-mixer-qt4 2.0.1+svn1856-
ii ffado-tools 2.0.1+svn1856-
ii libffado2 2.0.1+svn1856-
At first, the kernel modules for this device is "New Firewire Stack" (so-called by FFADO developer), firewire_ohci, firewire_core and crc_itu_t. Then I get much FFADO XRuns,
Secondly I use "Old Firewire Stack", ohci1394, raw1394, ieee1394 with the commands of rmmod and modprobe, these modules are standard in Lucid. Then I got a few FFADO XRUNs.
In both ways, I play the same music in the same sequencer.
In detail, please refer to the logs of "ffado-diag" and "jackd -v" I'LL attach. The "_old" means the old firewire stack and the "_new" means new one.
ProblemType: Bug
DistroRelease: Ubuntu 10.10
Package: libffado2 2.0.1+svn1856-
ProcVersionSign
Uname: Linux 2.6.35-22-generic i686
Architecture: i386
Date: Tue Sep 28 13:22:50 2010
InstallationMedia: Ubuntu-Studio 10.10 "Maverick Meerkat" - Beta i386 (20100902.1)
ProcEnviron:
LANG=ja_JP.utf8
SHELL=/bin/bash
SourcePackage: libffado
Changed in libffado (Ubuntu): | |
status: | New → Won't Fix |
If I understand the jackd logs correctly, jackd is running in the common SCHED_OTHER scheduling class rather than the SCHED_FIFO class. Have a look at http:// jackaudio. org/linux_ rt_config regarding the configuration steps to grant your account access to realtime scheduling classes. This is generally important for jackd in order to lower the likelihood of audio buffer underruns/ overruns.