On Fri, Sep 10, 2004 at 12:42:24AM -0400, Lee Revell wrote: > On Thu, 2004-09-09 at 23:29, Eric Dantan Rzewnicki wrote: > Eh, this is how free software works, the concept of wasting people's > time doesn't mean a lot. I spent a month banging my head against the > emu10k1 ALSA driver trying to figure out why the latency was 10 times > worse than in windows. Over a period of weeks I posted 5 or 6 crazy > theories to alsa-devel, all wrong. Turns out it was just a stupid bug > where a bunch of instances of SND_PCM_PERIOD_SIZE needed to be changed > to SND_PCM_PERIOD_BYTES. I submitted a patch and now the latency is > better than on Windows. > Moral of the story: in free software, the only person whose time you can > waste is your own, and it's only wasted time if you don't learn > anything. Thanks for the pep talk. :) I did learn a good bit over the past week. And I'm in a good place to build a lot of different sound tools for myself now. > This is very, very important, and also very good news! There have not > been a lot of reports yet from real linux audio users. So far UP users > seem to be reporting very good results, while SMP/HT users are still > seeing weird behavior. > Can you please try the following so I can report the results to Ingo: > Run "echo 0 > /proc/sys/kernel/preempt_max_latency" > Do some audio work for while > Copy /proc/latency_trace to a file and send it to me via private mail > Also, once your system seems to be running well, you should disable > latency tracing with "echo 0 > /proc/sys/kernel/trace_enabled". The > latency tracer itself can generates latencies of a few ms when it > updates /proc/latency_trace; this is not reported in the traces. Thanks for these notes. I'll get the latency trace to you this weekend. Thanks, Eric Rz.
