asked Jul 05 at 21:12 by halfshavedyaks (11)

edited Jul 10 at 15:58

I am evaluating the demo of BWS on linux.

I currently use Reaper.

I am finding that when playing a live software instrument from a midi keyboard that Bitwig can only manage one note without Xruns, and Reaper can manage 3 or 4 notes.

Same plugin, same keyboard input, same low latency Jack settings.

My panel CPU meter even registers a similar cpu usage in both cases, but with BWS I get xruns and with reaper i don't.

I am using a liquorix pre-empt kernel.

Now I know a fair bit about optimising for low latency performance, but in this case what is bugging me is the difference in performance between BWS and Reaper - its a deal breaker.

Since the only variable is the host DAW there must be something non-optimum in BWS. But I can't find any relevant settings in BWS to change, all that stuff is in jack and that is the same for both DAWs.

Does any one have any suggestions about what I might change?

Should there be specific real time priority settings for BWS set somewhere in the system?

EDIT: I also tested on MacOS and the difference there is much smaller - less than 10% I would guess, reaper is still better, but not by much.


I upgraded yesterday from bitwig 2.x to 3.x and experiencing xruns (same setup, just updated bitwig). I even double the buffer in jack (from 128 to 256) and still experiencing xruns.

BW team, you should consider trying to find what is eating our cpu. Very easy to reproduce, install BW 2 - add some poly, fm synths compare the dsp graph with BW 3.

Would be happy to buy the full version if you find the solution. Cheers


answered Jul 11 at 20:47 by eeight (11)

edited Jul 12 at 01:14

I was originally testing 2.5 but I have now tested BWS3 and they seem much the same. Exactly which version of BWS did you have better performance with? Was it earlier than 2.5?

  — (Jul 12 at 03:22) halfshavedyaks

2.5.1 are you pushing BWS to the lowest latency possible (setting jack as low as possible without having xruns, then update to BWS 3.x == xruns (again same setup + doubling the buffer == xruns too, so for me it's less optimized in BWS).

  — (Jul 12 at 03:30) eeight

my original comment was about 2.5.1 I had poor performance on that also.

I was testing by seeing how many notes I could play without xruns on a very cpu intensive synth sound (using u-he Diva)

I was testing mostly at 88.2khz 128 samples, which is a quite challenging setting. But the performance was obviously better on reaper on other settings too.

  — (Jul 12 at 11:35) halfshavedyaks

What kind of hardware are you running? How much memory? I would say 8GB min is needed if you want to do more than basic stuff. See this thread for setting up Jack: Try 44.1 khz, 256 frames, 3 buffers and go from there. Make sure "realtime" is checked in qjackctl. Does Guitarix running by itself work OK? You can also try running directly to ALSA in the Bitwig settings.


answered Jul 14 at 22:28 by dirtcooker (21)

Yes 8GB of RAM with a i7 - 4 cores. Like I said the same setup is working fine in BWS 2.5.x - the new version is causing xruns. Surely more CPU hungry. All other software are running fine (huge patch in pure data, guitarix etc). I reverted back to BWS 2.5.x for now.


answered Jul 15 at 02:36 by eeight (11)

Follow this question

By Email:

Once you sign in you will be able to subscribe for any updates here

Markdown Basics

  • *italic* or __italic__
  • **bold** or __bold__
  • link:[text]( "title")
  • image?![alt text](/path/img.jpg "title")
  • numbered list: 1. Foo 2. Bar
  • to add a line break simply add two spaces to where you would like the new line to be.
  • basic HTML tags are also supported



Asked: Jul 05 at 21:12

Seen: 301 times

Last updated: Jul 15 at 02:36