Code: Select all
cat /etc/security/limits.conf
@audio - memlock unlimited
@audio - nice -10
where set, which is obviously the case. Next important thing is to optimize the priority of the interrupt handlers of the soundcard. When the KXrepos are added this is done via the Rtirq script (https://alsa.opensrc.org/Rtirq) automatically (more or less).
The interrupt handler of the soundcard can also be set manually higher by hand. First check the running processes with
Code: Select all
cat /proc/interrupts
and localize the process for which the interrupts are increasing the fastest (soundcard should have a lot to do, so let's run a big project in your DAW).
If you have localized the interrupt handler for the soundcard let's check it's PID with
Code: Select all
pgrep irq/xx
Code: Select all
cat /proc/interrupts
Setting the priority higher works with
Code: Select all
sudo chrt -f -p 95 yy
Another thing which is important is to check that your audio interface connected to a USB bus where no other devices are connected. I my case it looks like:
Code: Select all
marco@fox:/etc$ lsusb
Bus 006 Device 002: ID 8087:8000 Intel Corp.
Bus 006 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
Bus 005 Device 002: ID 04e8:61f5 Samsung Electronics Co., Ltd
Bus 005 Device 001: ID 1d6b:0003 Linux Foundation 3.0 root hub
Bus 004 Device 009: ID 046d:c069 Logitech, Inc. M-U0007 [Corded Mouse M500]
Bus 004 Device 008: ID 09e8:0076 AKAI Professional M.I. Corp. LPK25 MIDI Keyboard
Bus 004 Device 007: ID 0835:8502 Action Star Enterprise Co., Ltd
Bus 004 Device 006: ID 0835:8500 Action Star Enterprise Co., Ltd
Bus 004 Device 005: ID 046a:0011 Cherry GmbH G83 (RS 6000) Keyboard
Bus 004 Device 004: ID 0835:8501 Action Star Enterprise Co., Ltd
Bus 004 Device 003: ID 0835:8500 Action Star Enterprise Co., Ltd
Bus 004 Device 002: ID 2109:3431 VIA Labs, Inc. Hub
Bus 004 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
Bus 001 Device 002: ID 8087:8008 Intel Corp.
Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
Bus 003 Device 001: ID 1d6b:0003 Linux Foundation 3.0 root hub
Bus 002 Device 002: ID 1686:014f ZOOM Corporation
Bus 002 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
After doing all the appropriate changes I still get xruns with buffer sizes below 512 at DSP loads of ~60-85%. And the strange thing is that I get more xruns when switching desktop windows or browsing in chromium. Especially using the scroll wheel of the mouse seems to trigger xruns. When using 512 samples everything works fine, but of course adding more vst instruments will cause problems even at this buffer size.
Does anyone know where this might come from or what else can I check?
@JackWinter: If I have written bogus somewhere please correct me.