Modulation CPU usage

Help, Support & Bugs
1

Why does an AHDSR envelope use more CPU than an mpReverb or a CabinetSimulator?

I realized that the new bundled instruments use a lot of CPU, so I thought I check what is the cause. I loaded the Acoustic Guitar. First, I obviously thought that the DSP are the reason, so I disabled one by one each DSP. CPU usage went down, as expected. However, the biggest increase in CPU usage I saw after disabling the AHDSR envelope!

I suspect something non-intended going on here.

2

Interesting

3

More interesting observations:

  1. Open Renoise
  2. Load a break as instrument 1
  3. CPU usage (without playing) is 4.7%
  4. Add a AHDSR
  5. CPU usage (without playing) is 14%
  6. Play a note
  7. CPU usage (while playing) is 11%
  8. Delete AHDSR
  9. Add envelope
  10. CPU usage (without playing) is 23.8%
  11. Play a note
  12. CPU usage (while playing) is 17.3%

So there are two things here:
a. Why do the modulation devices use so much CPU?
b. Why do they use less (but still a lot) when actually processing sound?

Tested on an Asus 1005HA netbook with elementary OS.

4

Ah! It’s a GUI problem! Switching to another tab reduces CPU immediately.

There is seriously something fishy going on with the GUI under Linux, it uses a lot of CPU!

5

It’s not only on Linux. same behavior here on Windows.

6

Mmh… a lot of things in the new Renoise use a lot of CPU. The modulation, the phrases… I think we now need a proper freeze function ore than ever before…

7

On windows vista 32 bit, core2 duo, 4 gig ram;

  1. Open Renoise

  2. Load a break as instrument 1

  3. CPU usage (without playing) is 2.3% (fluctuating up to 4.4% max)

  4. Add a AHDSR

  5. CPU usage (without playing) is 3.9% (fluctuating up to 6.1% max)

  6. Play a note

  7. CPU usage (while playing) is 10.2% (fluctuating up to 11.4% max)

  8. Delete AHDSR

  9. Add envelope

  10. CPU usage (without playing) is 9.5% (fluctuating up to 10.4% max)

  11. Play a note

  12. CPU usage (while playing) is 14.1% (fluctuating up to 15.9% max)

Note I’m running default of 10 tracks with eq10 + gainer device on all of em, plus hydra on the first track routed to the gainers. Also a multiband vst on the master.

I had the instrument editor expanded to a second monitor while trying this.

8

Freezing will not solve the fundamental problem .
This sounds serious

9

The modulation graph preview thing uses quite a lot of CPU, but it adapts with the number of modulation devices and stuff so that it never uses “too” much CPU. Does so to preview graphs as snappy as possible.

So to compare modulation vs. non modulated GUI make sure the modulation graph is hidden.

10

Would a better graphics card make a difference in Renoise performance?

11

May I ask why the visiualization of the modulation graphs takes so much cpu ?
Is it because of the accurate display , if so wouldn’t it be possible for the user to determine the acurateness (visually ) to preserve some cpu .

12

Maybe, for things like this, an option to hide when song is playing might be useful.
So you can always see stuff when you are working on an element, but it’s toggled off when you are running the whole shebang - when CPU really counts (in most cases).

13

yes …
I know for example that in zebra 2 , when going to the multi envelope window and setting the pointer to accurate it also consumes more cpu …the user has the option to use accurate or less accurate (only for the pointer/indicator that is , the envelopes stay accurate )