Daniel Drake wrote: > Hi Victor, > > Thanks a lot for the feedback. > > On Thu, 2008-08-07 at 21:45 +0100, victor wrote: > >> One of the things I have been playing with is a little MIDI file >> player >> (one of the test/example activities in >> devel.laptop.org/activities/csndsugui), >> which uses a soundfont synthesis engine. On the older system, I >> can play most files with only the occasional dropout, generally >> quite solidly. But on the later (2232 and 2263), I get many more >> dropouts >> > > We are already aware of an audio performance regression and believe it > be related to 2 things: > - hal polls our battery a lot more than it used to, even when fully > charged, and EC commands disable interrupts and cause sound stutters. > (I'm working on fixing hal, I sent patches upstream) > - the kernel upgrade from 2.6.22 to 2.6.25 also included some changes > (which we haven't identified yet) which cause these problems. > Downgrading to 2.6.22 restores the previous audio performance. > > Thanks for pointing out your test-case though! So far we have been > reproducing these issues by using TamTamMini, TamTam is indeed > affected. :( > > Here is the relevant ticket: > http://dev.laptop.org/ticket/7603 > Contributions welcome! It is a tricky one. > > Thanks, > Daniel > Here an other observation which might have something to do with this. In joyride-2266 (booted from SD card) I noticed that there is a lot of logging of the traffic to the EC. Just do dmesg and you see a burst of about 18 olpc-ec: messages approximately every 30 seconds. Can this extra logging cause hic-ups ?? This might be a red herring, but you never know ....
Ton van Overbeek _______________________________________________ Devel mailing list [email protected] http://lists.laptop.org/listinfo/devel
