I must admit that this whole thread confuses me. I've tried to read the entire thread a couple of times
This is what I know.
It's probably a very good idea to keep your /tmp mounted as a tmpfs (ramdisk). It's a filesystem meant for temporary files, and it typically doesn't get big, on my system right now after a weeks uptime 304MB. On my system it's taken care of the distro (archlinux), I have no /etc/fstab entry for it. The mount command shows this: tmpfs on /tmp type tmpfs (rw,nosuid,nodev)
JACK prefers to use /dev/shm, as it's very fast for I/O. Again I have no fstab entry for it as it's taken care of my distro. mount shows: tmpfs on /dev/shm type tmpfs (rw,nosuid,nodev). With JACK and REAPER running it's using 65MB, though a lot of those are leftover files after killing LinVst that also uses it.
IIRC, a tmpf defaults to half available ram, so you can use the size option if you want to make that bigger or smaller.
I think if you use gentoo, then you have to either use some overlay that makes sure this is all done, or you have to make sure to do it yourself
Regarding the realTimeConfigQuickScan script. I get the following "not good". I'll comment after each one:
Code: Select all
Checking CPU Governors... CPU 0: 'powersave' CPU 1: 'powersave' CPU 2: 'powersave' CPU 3: 'powersave' CPU 4: 'powersave' CPU 5: 'powersave' CPU 6: 'powersave' CPU 7: 'powersave' - not good
Set CPU Governors to 'performance' with 'cpufreq-set -c <cpunr> -g performance'
See also: http://linuxmusicians.com/viewtopic.php?f=27&t=844
I use the Intel pstate driver. AFAIK you can't change governor on it. What you can do on most systems is to write 0 as a dword into /dev/cpu_dma_latency and keep the handle open. On my i7-2600k it doesn't seem to make a difference, on my i7-4700HQ quite a lot. This effectively makes the CPUs stay in C0/C1 states.
Code: Select all
Checking swappiness... 60 - not good
** vm.swappiness is larger than 10
set it with '/sbin/sysctl -w vm.swappiness=10'
See also: http://linuxmusicians.com/viewtopic.php?f=27&t=452&start=30#p8916
I've played with swappiness and never found it useful. I still run into occasional "swap storms" when I don't pay attention. The best for me is to kill the browsers every few days to regain ram
Code: Select all
Checking checking sysctl inotify max_user_watches... < 524288 - not good
increase max_user_watches by adding 'fs.inotify.max_user_watches = 524288' to /etc/sysctl.conf and rebooting
For more information, see http://wiki.linuxaudio.org/wiki/system_configuration#sysctlconf
Here I have 8192, should I increase this?
Code: Select all
Checking access to the high precision event timer... not readable - not good
/dev/hpet found, but not readable.
make /dev/hpet readable by the 'audio' group
For more information, see http://wiki.linuxaudio.org/wiki/system_configuration#hardware_timers
Checking access to the real-time clock... not readable - not good
/dev/rtc found, but not readable.
make /dev/rtc readable by the 'audio' group
For more information, see http://wiki.linuxaudio.org/wiki/system_configuration#hardware_timers
Regarding the rtc clock it's most likely not used at all nowadays. cat /proc/interrupts | grep rtc showsthat it's fired exactly once on my system since boot. hpet probably also doesn't have to be accessible by the user as AFAIK JACK uses hrtimers built into the kernel.
Code: Select all
Checking whether you're in the 'audio' group... no - not good
add yourself to the audio group with 'adduser $USER audio'
I don't use an "audio" group at all. The one group I've added to my system is "realtime", and I hope this becomes standard on Archlinux some day. The people behind systemd/policykit/archlinux would prefer that the audio group isn't used to give access to devices, as that breaks how they conceive of multi seat computers.
I think it would be exceedingly hard to make a script like realTimeConfigQuickScan perfect. Maybe best to take it as suggestions and not as the gospel truth.