Hi Peder, Mark, On Wed, 2005-09-28 at 17:03 +0200, Peder Hedlund wrote: > > I believe that you are using anticipatory. > > Yes, your using the one in brackets Yes, I've noted it now ;-) > >I don't know which one is best for low latency. > > I don't either, but judging from this it might be anticipatory: > http://kerneltrap.org/node/616. > I really doubt (from an ordinary audio users POV) you'll see > that much difference in latency tough. I'd rather make sure my hdparm > values are correct. I've jet optimised my hd with hdparm. Thanks to remember this though. > > You can try each one (I think) by adding a boot time option to grub.conf > > elevator=deadline > > or > > elevator=cfq > > or you can change the running scheduler w/o rebooting by doing > echo deadline > /sys/block/hda/queue/scheduler Ok I've tried and both methods work. Before I was bad spelling the name of the scheduler so it weren't changed. (I'm not sure if I right spelled this sentence, though :-( ). To follow Mark's advice to experiment myself I done a little, non scientific, test. I've tried to uninstall and reinstall (with apt) openoffice (~ 150 MB) while listening a good album (say Holy Diver, Dio) with beep-media-player. I've found that the anticipatory scheduler gives lots of gaps (too much) in the music during the process. The deadline scheduler gives less gaps, but there are at least a long gap (~ 0.5 sec) during the uninstal-install process. If, in the meantime, I also open/close evolution the gaps become more and more long. With the cfq scheduler instead I don't have a single (audible) gap in the music, also using evolution or other programs during the uninstall-install process. The noop scheduler is the worse in my test. This is only my little test. Probably if your aim is to do multi-track recording with ardour you can have opposite results (regarding wich scheduler is the best), or the same, I don't know. I've reported it only for the record. > For latency, I'd run the latest 2.6.13 (it's .2 now). > 2.6.12 had some bugs in its rlimits code that's fixed in 13. > Also make sure you have the patched PAM and an adusted > /etc/security/limits.conf to make proper use of rlimits. And yes I'm going to try the 2.6.13 too. Do you know if I can use the realtime-lsm module with the .13? I don't care about security risk on this machine. Anyhow, many thanks for the useful answer you give me so far ;-). Best Regards, ~ Antonio
