On Sat, 23 Dec 2017 02:37:18 +0100, Ralf Mardorf wrote:
On Fri, 22 Dec 2017 20:54:47 +0100, LX wrote:
On Fri, 22 Dec 2017 06:33:11 +0100, Ralf Mardorf wrote:
Intel(R) Core(TM) i5-3317U CPU @ 1.70GHz 4.14.6-rt7-1-rt [root@pill-mobile4 gimmeapill]# cyclictest -S -m -p98 # /dev/cpu_dma_latency set to 0us policy: fifo: loadavg: 0.10 0.06 0.02 1/161 521 Max: 15
Intel(R) Celeron(R) CPU G1840 @ 2.80GHz 4.14.6-rt7-1-rt cyclictest -S -m -p98 WARN: open /dev/cpu_dma_latency: Permission denied policy: fifo: loadavg: 0.13 0.09 0.02 1/208 4690
T: 0 ( 1245) P:98 I:1000 C:35539474 Min: 1 Act: 31 Avg: 27 Max: 83
Hi,
does the CPU make such a big difference? If so, I'll order another CPU today. Or is it the combination of CPU and mobo that does cause such a big difference?
Is there a reason to run cyclictest as root? We do audio work as an user without root privileges.
This short run already seems to answer my questions:
[root@archlinux rocketmouse]# uname -rm 4.14.6-rt7-1-rt x86_64 [root@archlinux rocketmouse]# cyclictest -S -m -p98 # /dev/cpu_dma_latency set to 0us policy: fifo: loadavg: 0.00 0.02 0.00 1/254 10107
T: 0 (10106) P:98 I:1000 C: 8583 Min: 1 Act: 1 Avg: 1 Max: 6 T: 1 (10107) P:98 I:1500 C: 5720 Min: 1 Act: 1 Avg: 1 Max: 6 ^C[root@archlinux rocketmouse]#
However, regarding my questions the manpage of cyclictest isn't helpful.
PS: What does it all mean? A cheap Intel(R) Celeron(R) CPU G1840 @ 2.80GHz has got less latency, than a much more expensive Intel(R) Core(TM) i5-3317U CPU @ 1.70GHz? How does it affect audio work? What is the relevance of cyclictest? Is the result somehow related to audio latency and/or MIDI jitter?