On Wed, Jul 21, 2010 at 04:11:07PM +0400, Dmitrij D. Czarkoff wrote: > Jacob Meuser <[email protected]> wrote: > > > you're saying the volume made a difference in how often there were > > underruns? that is quite odd. hmmm. > > Well I'm saying that I had less underruns while being at 150/255 volume. It > might be a coincidence. > > > > At the moment of volume switching I also hear the drops (as far as I can > > > get, > > > the drops of a higher of switching volumes either on gettting volume > > > lower or > > > higher). > > > > that is strange too. I have, somewhere, a program that twiddles every > > control on the mixer as fast as possible, several thousand mixer set/get > > cycles a second, and it hassn't caused dropouts on machines I've run > > it on. > > Well, that's what I'm quite sure about. The drops accure on every volume > switch I performed. > > > do you have clock issues? are you running ntpd? > > I'm running ntpd and it is quite active in switching time. > > Well, after pkilling ntpd I got 13 drops (with 8 of them long enough to > distinguish start and end speaker "cklicks") during 3 minutes with actually > close output: > > % ./audrops > pre=16 ch=2 bpf=4 block_size=4096 rate=48000 block_usec=21333 > early return at 1279713267.091162: 399 < 21333 > early return at 1279713267.091246: 84 < 21333 > late return at 1279713267.968778: 558599 > 21333 > late return at 1279713276.422734: 564385 > 21333 > late return at 1279713283.216141: 573650 > 21333 > early return at 1279713283.219052: 2911 < 21333 > late return at 1279713293.508187: 561489 > 21333 > late return at 1279713313.472366: 578602 > 21333 > late return at 1279713330.094540: 560445 > 21333 > early return at 1279713330.094700: 160 < 21333 > early return at 1279713330.094787: 87 < 21333 > early return at 1279713330.094890: 103 < 21333 > early return at 1279713330.095015: 125 < 21333 > early return at 1279713330.095142: 127 < 21333 > early return at 1279713330.095211: 69 < 21333 > early return at 1279713330.095286: 75 < 21333 > early return at 1279713330.095353: 67 < 21333 > early return at 1279713330.095422: 69 < 21333 > early return at 1279713330.095490: 68 < 21333 > early return at 1279713330.095558: 68 < 21333 > early return at 1279713330.095626: 68 < 21333 > early return at 1279713330.095694: 68 < 21333 > early return at 1279713330.095760: 66 < 21333 > early return at 1279713330.095828: 68 < 21333 > early return at 1279713330.095895: 67 < 21333 > early return at 1279713330.095963: 68 < 21333 > early return at 1279713330.096030: 67 < 21333 > early return at 1279713330.096097: 67 < 21333 > early return at 1279713330.096165: 68 < 21333 > early return at 1279713330.096233: 68 < 21333 > early return at 1279713330.096301: 68 < 21333 > early return at 1279713330.096368: 67 < 21333 > early return at 1279713330.096436: 68 < 21333 > early return at 1279713330.096503: 67 < 21333 > late return at 1279713353.314772: 569539 > 21333 > early return at 1279713353.321255: 6483 < 21333 > late return at 1279713355.167678: 566406 > 21333 > early return at 1279713355.177299: 9621 < 21333 > late return at 1279713372.491682: 567395 > 21333 > early return at 1279713372.500329: 8647 < 21333 > late return at 1279713400.362901: 555313 > 21333 > late return at 1279713412.040398: 563321 > 21333 > early return at 1279713412.040537: 139 < 21333 > early return at 1279713412.040624: 87 < 21333 > early return at 1279713412.040693: 69 < 21333 > early return at 1279713412.040763: 70 < 21333 > early return at 1279713412.040830: 67 < 21333 > early return at 1279713412.040904: 74 < 21333 > early return at 1279713412.041010: 106 < 21333 > early return at 1279713412.041079: 69 < 21333 > early return at 1279713412.041155: 76 < 21333 > early return at 1279713412.041221: 66 < 21333 > early return at 1279713412.041289: 68 < 21333 > early return at 1279713412.041357: 68 < 21333 > early return at 1279713412.041425: 68 < 21333 > early return at 1279713412.041491: 66 < 21333 > early return at 1279713412.041560: 69 < 21333 > early return at 1279713412.041628: 68 < 21333 > early return at 1279713412.041696: 68 < 21333 > early return at 1279713412.041764: 68 < 21333 > early return at 1279713412.041832: 68 < 21333 > early return at 1279713412.041899: 67 < 21333 > early return at 1279713412.041966: 67 < 21333 > early return at 1279713412.042034: 68 < 21333 > early return at 1279713412.042101: 67 < 21333 > early return at 1279713412.042169: 68 < 21333 > early return at 1279713412.042237: 68 < 21333 > early return at 1279713424.960047: 7609 < 21333 > late return at 1279713427.759535: 559467 > 21333 > late return at 1279713440.156372: 561392 > 21333 > ^Cpre=16 ch=2 bpf=4 block_size=4096 rate=48000 block_usec=21333 > bytes written = 34062336 > bytes processed = 33849344 > bytes errors = 204800 > bytes buffered = 8192 > 34062336 == 34062336 ? > run time = 183.256628 s > avg rate = 46177 > > > this is about the simplest possible audio application. no reading > > data from disk, not synthesizing the samples. I don't see how > > this could have underrun so much. what else was running while you > > ran this? > > Aside from default processes of 4.7 I had ifstated, X11, cwm, ntpd, rtorrent > (with 7.1/0.6 kbps loadi) and a shell script that sleeps 30 seconds and sends > ifconfig command to the system after that. That's all. > > > one final question, do you have any sort of power management features > > enabled in the BIOS? > > Well, my BIOS is very tiny, it doesn't ask about power management. Still, I > have apmd running "Cool mode". > > > hmmm, if the codec is somehow under powered, I guess that could explain > > the correlation between higher volume and more dropouts? maybe? > > Don't think so as I had Linux on this box before, and had no single problem > with sound. The default OS was Windows, but I only had it on twice, the last > time on power appliance. > > > iirc, you have an eapd mixer control. have you tried switching that > > to off? I've heard rumors that these are sometimes inverted ... > > eapd (external amp power down) is a tricky name. > > I tried turning it off. That muted my system. After turning on I returned to > the previous state. > > By the way, do You actually know, what is eapd supposed to be used for?
yes, it's a power saving feature. it turns off the power to an amplifier. that's why setting it to "off" mutes your outputs. you probably need the changes in src/sys/dev/pci/azalia.c rev 1.169. I thought that was in 4.7, but now that I look, it was a bit after. http://www.openbsd.org/cgi-bin/cvsweb/src/sys/dev/pci/azalia.c.diff?r1=1.168;r2=1.169 -- [email protected] SDF Public Access UNIX System - http://sdf.lonestar.org
