From mboxrd@z Thu Jan 1 00:00:00 1970 From: Benno Senoner Date: Sat, 28 Aug 1999 19:14:29 +0000 Subject: Low-latency patches working GREAT (<2.9ms audio latency), see testresults ,but ISDN troubles Message-Id: List-Id: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: linux-sound@vger.kernel.org Hi, I benchmarked Mingo's latest low-latency patches (2.2.10-N6 a bit modified) The patches give me excellent results with sporadic very 2.9ms peaks ! See the testresults here: http://www.gardena.net/benno/linux/audio/2.2.10-n6b/index.html You can get the patch here: http://www.gardena.net/benno/linux/audio/patches/lowlatency-2.2.10-N6B.patch More details on my audio page. Unfortunately the patch has still some problems , not latency-related: - The ISDN hisax driver (my card is a Fritz classic) crashes the kernel at modprobe hisax.o (does not happen on an unpatched 2.2.10 kernel) Can someone of the ISDN maintainers please reproduce/fix this ? (maybe a race at module initialization ?) - The disk performance decreases by 10-25% when I increase the CPU load in the "latencytest" bench. (On light CPU load there are no disk performance differences, maybe this is related to higher scheduling overhead) I think most of us want to have these "low-latency" features in the upcoming 2.4 kernel since it will make Linux a very good _MULTIMEDIA_OS_. With Mingo's patches the Linux low-latency performance comes very close to BEOS, and is much much better (3-4 times) Windows on the same hardware. It's now time to stress audio-software vendors to port their cool apps to Linux. comments ? PS: To Microsoft's Anti-Linux team: just download the patch and compare the performance with your crappy DirectX API :-) regards, Benno. -- Benno Senoner E-Mail: sbenno@gardena.net Linux scheduling latency benchmarks http://www.gardena.net/benno/linux/audio