VST uses more CPU when not playing notes

shambles07 / foo-yc20

Automatically exported from code.google.com/p/foo-yc20

Other

0 stars 0 forks source link

VST uses more CPU when not playing notes #2

Closed GoogleCodeExporter closed 8 years ago

GoogleCodeExporter commented 8 years ago

What steps will reproduce the problem?
1. Load the VST plug-in.
2. Play a few notes, CPU hovers at e.g. 16.3%.
3. Stop playing any notyes, CPU hovers at 28.6%.

What is the expected output? What do you see instead?
I would expect the plug-in to use less CPU when not playing any notes, or 
perhaps the same, but certainly not more.

What version of the product are you using? On what operating system?
foo-yc20 1.2.0 in REAPER 3 on Windows XP Professional SP3.

Please provide any additional information below.
An educated guess is that denormals are involved here.

Original issue reported on code.google.com by Tal...@gmail.com on 21 Jan 2011 at 12:18

GoogleCodeExporter commented 8 years ago

The CPU usage is expected to be the same regardless of the amount of keys 
pressed down (0..61). This does sound like a denormal issue. 

What CPU is this? 

Does switching the realism switch to full-on (completely down) make a 
difference?

Original comment by sampo.sa...@gmail.com on 21 Jan 2011 at 12:24

Added labels: Denormals

GoogleCodeExporter commented 8 years ago

The CPU is an Intel Core 2 Duo E6300 1.86GHz.

If I set the realism switch to about 0.84 or higher, I get more or less 
constant CPU usage. Below 0.84 I again get an increased CPU usage when not 
playing any notes.

Original comment by Tal...@gmail.com on 21 Jan 2011 at 12:35

GoogleCodeExporter commented 8 years ago

Yep. That's the cutoff point where the drawbar bleed is activated. I'll see 
what I can do about the denormals. Thanks for the report!

Original comment by sampo.sa...@gmail.com on 21 Jan 2011 at 12:40

Changed state: Accepted

GoogleCodeExporter commented 8 years ago

Can you try the attached VST dll? It should have denormal protection in place.

Original comment by sampo.sa...@gmail.com on 21 Jan 2011 at 4:10

Changed state: Started
Added labels: OpSys-Windows

Attachments:

FooYC20.dll

GoogleCodeExporter commented 8 years ago

Yay, it works! :-) It now has a pretty constant CPU usage of around 11.9%.

Cool, thanks!

Original comment by Tal...@gmail.com on 21 Jan 2011 at 4:21

GoogleCodeExporter commented 8 years ago

Cool. I'll build a 1.2.1 release with the fix. Thanks for finding it!

Original comment by sampo.sa...@gmail.com on 21 Jan 2011 at 4:25

Changed state: Fixed