Arthur Marsh wrote, on 06/02/11 16:06: > Arthur Marsh wrote, on 06/02/11 12:08: >> Arthur Marsh wrote, on 05/02/11 17:30: >>> Hi, I've had problems lately with recent kernels 2.6.37 and later, but >>> haven't been able to pinpoint a specific change with git-bisect. >>> >>> MIDI playback either through xmms or aplaymidi won't keep regular time, >>> sounding weird going faster and slower under any kind of system load >>> except when nothing else is running. >>> >>> My alsa-info.sh results are at >>> >>> http://www.alsa-project.org >>> /db/?f=e6a1108957098461ebbca54cc342f616b03b12df >>> >>> Has anyone experienced this kind of problem? >>> >>> Arthur. >> >> Earlier, Takashi Iwai suggested: >> >> Well, it implies that hrtimer is broken on your hardware. >> >> Just add a module option timer_limit=3 to snd-timer, i.e. adding a file >> containing below to /etc/modprobe.d/*. >> >> options snd-timer timer_limit=3 >> >> >> so I modified my /etc/modprobe.d/sound.conf to include: >> >> "options snd-timer timer_limit=3" as below: >> >> alias snd-card-0 snd-emu10k1 >> options snd-emu10k1 index=0 >> options snd-timer timer_limit=3 >> >> The problem still appears to be persisting, so I might try: >> >> options snd-timer timer_limit=2 > > I've since upgraded to ALSA 1.0.24 (no change), then tried setting > timer_limit=2 (no change), then tried setting timer_limit=1 (better, but > some slow downs like when trying to bring up a window to compose this > message, or running aptitude -u). > > Current alsa-info.sh output is at: > > http://www.alsa-project.org/db/?f=32eda5c522289fb30ef704fe73efa68314ce91d3 > I've tried setting "options snd-timer timer_limit=x" where x is anywhere from 5 down to 0, and seeing either: $ cat /proc/asound/seq/timer Timer for queue 0 : HR timer Period time : 0.004000250 Skew : 65536 / 65536 or "system timer" in place of "HR timer". I've also tried adding "lapic" to the kernel command line, which resulted in the following in dmesg: [ 0.000000] Using APIC driver default [ 0.000000] Local APIC disabled by BIOS -- reenabling. [ 0.000000] Found and enabled local APIC! [ 0.000000] Kernel command line: BOOT_IMAGE=/vmlinuz-2.6.38-rc3-git4 root=UUID=96c96a61-8615-4715-86d0-09cb8c62638c ro lapic kexec_jump_back_entry=0xff999999 kexec_jump_back_entry=0xf3b3f3b6 [ 0.020674] Enabling APIC mode: Flat. Using 0 I/O APICs and: Switching to clocksource jiffies and also tried a kernel with CONFIG_PREEMPT=y In all cases, under sufficient load (which might be just running aptitude -u), the tempo of the MIDI file play-back slows right down. Any further suggestions welcome. Arthur. ------------------------------------------------------------------------------ The modern datacenter depends on network connectivity to access resources and provide services. The best practices for maximizing a physical server's connectivity to a physical network are well understood - see how these rules translate into the virtual world? http://p.sf.net/sfu/oracle-sfdevnlfb _______________________________________________ Alsa-user mailing list Alsa-user@xxxxxxxxxxxxxxxxxxxxx https://lists.sourceforge.net/lists/listinfo/alsa-user
