Hi, I have major sound skipping problems on FreeBSD 6.0. I checked the mailing list archives and found a related thread: http://lists.freebsd.org/pipermail/freebsd-current/2005-June/051103.html To quote Jeff Roberson: > I have a patch that should greatly improve the sound skipping problems > people have under heavy io load. Several people sent me traces that > showed the buf daemon running for hundreds of milliseconds with Giant > held, which can hold up the pcm code. The patch is available at: > > http://www.chesapeake.net/~jroberson/flushbuf.diff The problems are definately correlated to io load, however I can't say that I have HEAVY io loads. A simple: # sync;sync;sync; will already cause the sound to skip. I have DMA enabled on all drives, and it seems the above patch is already merged into FreeBSD 6.0-STABLE. This leaves me at a loss, and I don't know what else to try... Does anybody have any ideas of what I could do to solve this problem? Thanks in advance, Sebastiaan van Erk root@piglet(ttyp9:92:0):~# uname -a FreeBSD piglet.sebster.com 6.0-STABLE FreeBSD 6.0-STABLE #1: Sat Nov 5 23:42:18 CET 2005 root@piglet.sebster.com:/usr/obj/usr/src/sys/PIGLET i386 root@piglet(ttyp9:93:0):~# cat /dev/sndstat FreeBSD Audio Driver (newpcm) Installed devices: pcm0: <VIA VT8237> at io 0xec00 irq 22 kld snd_via8233 (5p/1r/0v channels duplex default)
On Sun, Nov 06, 2005 at 12:39:02PM +0100, Sebastiaan van Erk wrote:> Hi, > > I have major sound skipping problems on FreeBSD 6.0. I checked the > mailing list archives and found a related thread:...> > Does anybody have any ideas of what I could do to solve this problem? >You could try to set hint.pcm.0.buffersize="16384" in /boot/loader.conf . It solved the problem for me. -- Markus
On Sun, 06 Nov 2005 12:39:02 +0100 Sebastiaan van Erk <sebster@sebster.com> wrote:> Hi, > > I have major sound skipping problems on FreeBSD 6.0. I checked the > mailing list archives and found a related thread: > > http://lists.freebsd.org/pipermail/freebsd-current/2005-June/051103.html > > To quote Jeff Roberson: > > > I have a patch that should greatly improve the sound skipping > > problems people have under heavy io load. Several people sent me > > traces that showed the buf daemon running for hundreds of > > milliseconds with Giant held, which can hold up the pcm code. > > The patch is available at: > > > > http://www.chesapeake.net/~jroberson/flushbuf.diff > > The problems are definately correlated to io load, however I can't > say that I have HEAVY io loads. A simple: # sync;sync;sync; will > already cause the sound to skip. > > I have DMA enabled on all drives, and it seems the above patch is > already merged into FreeBSD 6.0-STABLE. This leaves me at a loss, > and I don't know what else to try... > > Does anybody have any ideas of what I could do to solve this > problem? > >Recompile your kernel with "options PREEMPTION", and apply this patch: http://people.freebsd.org/~ariff/snd_RELENG_6_0_20051030_058.diff -- Ariff Abdullah MyBSD http://www.MyBSD.org.my (IPv6/IPv4) http://staff.MyBSD.org.my (IPv6/IPv4) http://tomoyo.MyBSD.org.my (IPv6/IPv4)
Hi, Thanks for the tip, this seems to do the trick. Tested it with /usr/ports/sysutils/stress: root@piglet(ttyp7:42:0):/shared# stress --cpu 8 --io 4 --vm 2 --vm-bytes 128M --hdd 4 --timeout 10m stress: info: [2439] dispatching hogs: 8 cpu, 4 io, 2 vm, 4 hdd and heard no more skips. Greetings, Sebastiaan van Erk Markus Trippelsdorf wrote:> On Sun, Nov 06, 2005 at 12:39:02PM +0100, Sebastiaan van Erk wrote: > >>Hi, >> >>I have major sound skipping problems on FreeBSD 6.0. I checked the >>mailing list archives and found a related thread: > > ... > >>Does anybody have any ideas of what I could do to solve this problem? >> > > You could try to set hint.pcm.0.buffersize="16384" in /boot/loader.conf . > It solved the problem for me.