Less CPU hungry VCV Rack alternatives?

(Tugrikyan (OTK)) #41

Thanks a thousand times, Jim, my first impressions while testing your new 5-XP version are very positive - it’s really a huge CPU saver (at least for my notebook - Win7/64). The only serious problem for now is that this new version somehow can not save settings after restart+always loses register info (and favorites list too :(). But in fact I could take that in exchange for better productivity :slight_smile:

(Jim T) #42

That’s irritating. I just checked on my windows 10 laptop and I can’t see the same settings issue at all. There might be something wrong with the settings.json - would you mind:

  • close rack
  • find the settings.json in your Documents/Rack folder
  • move it out of that folder
  • restart rack
  • login
  • close/repoen rack

This is the only thing I can think of right now. Also, is there anything in the log.txt file next to your settings.json that might shed light on what’s going on?

(Jim T) #43

Ok, we’ve been testing this a bit, but it looks like it’s fairly stable. There’s been an issue with settings not being loaded/saving but it’s not general and I’ve not tracked that down.

So please have a go, it definitely makes a difference to cpu usage on that UI thread. I ran your patch on a 2014 quad core 13" mbp, and it only worked when I reduced the framerate to 10fps, regardless of the number of threads thrown at it. This is interesting as it means there’s something else going on here, particularly on the mac, that is affecting stuttering.


(Nik Jewell) #44

Jim is too modest by half - this is an extraordinary achievement.

On the i9 MBP, running at 10 FPS my CPU temperature for the patch has gone from 98 degrees to 52 degrees.

The GPU has gone from 67 degrees to 39 degrees.

The fans are running at default 2k, instead of nearly 6k, the CPU has gone from turbo boosted 3.7GHz to comfortable 2.5 Ghz.

Simply incredible.

(Stephan) #45

@JimT I just tried your experimental version,
it really improves the performance on my crappy intel celeron N2940 Laptop with onboard Intel HD graphics,

but it also adds a real lag to the GUI respond times, even when I set it to 144hz there is still a lag
of about 1 second untill the GUI responds now. this way it is almost unusable here :cry:

I hope this will change in further updates

(Jim T) #46

sorry it’s playing up. no idea what would cause that, literally nothing in there is new. the FPS limiting code is already in there, I’m just making it adjustable :thinking:

out of interest, could you download the previous experiment and see if it does the same?

(Tugrikyan (OTK)) #47

I am back after 3 or 4 hours of testing and now it’s working fine - somehow/unexpainably all my initial problems with settings & fav’s are gone (I just spent another 15 min to resave them - no prob ;)).
And I have to reiterate once more - this last XP-version is just excellent (and, BTW, previous one also was very good)! I can’t tell for others, but my notebook is now eating happily almost everything (I mean various patches) without serious CPU/stutter problems.
Just FYI: my practical tests show that best settings for my note are:
Threads - 2 (max 3, 4 and more resulted in stutters), FPS=30 (10 is NOT GOOD IMHO, it makes my audio somehow a bit freezing) and finally optimal BlockSize for Audio now is 512 while before (about 2 months of using VCV) I always opted for 4096 or 2048 :slight_smile:
What can I say more…Just thanx again, Tim, you are real magician!
P.S. I would suggest to Mr.Belt to learn from Tim how to make efficient & much more user-friendly releases of VCV. Pardon my french :wink:

(Andrew Belt) #48


(Tugrikyan (OTK)) #49

OK, Andrew, I am at least 20 years older than you, so, please, be a little more polite :wink:
Jokes apart, I would like to express my deep gratitude and respect for your beautiful product. I spent many years using Reaktor every day, but for last two months I almost forgot it :slight_smile:

(Tugrikyan (OTK)) #50

Oops, sorry for misspelling your name, Jim :))

(Andrew Belt) #51

Just kidding, I don’t care about those things so just giving you a nudge.

However, what I do care about is ageism, so please cut that out or I will actually remove you from this community.

(Tugrikyan (OTK)) #52

Well, forget it, Andrew, I didn’t even think about those stupid things (I mean age differences ;).

(Nik Jewell) #53


I can’t replicate any lagginess and can drag a large active Fullscope around the screen at 10fps.

I wonder if this has anything to do with onboard graphics vs a discrete GPU. Unfortunately I don’t know any way of forcing OS X to use the onboard graphics to test, you can only force the DGPU I think.


I believe you can force card usage with https://gfx.io/

at least that is how i force the discrete card to be used

(Stephan) #55

after a restart of VCV I couldn’t reproduce the lag,
I will see if it happens again and report back

(Nik Jewell) #56

Many thanks. Unfortunately, that doesn’t seem to be working in Mojave - when I try to force the integrated graphics it immediately switches the DGPU on.

(Stephan) #57

today I tried the 4th jan 2 patch with my PC,
and I must say my Ryzen CPU perfomes quiet well
the cpu meter shows about 370 to 440 ms still available
it uses 11% cpu and 37% of my gpu nvidia gtx 1050
and yet I didn’t use the experimental version of VCV.
I will try that later.

(Stephan) #58

Now I tried the experimental version of VCV with my Ryzen 1700 PC (8 cores /16 threads)

— omg this is amazing —

I can paly the 4th jan 2 patch here in 96000Hz with 10 threads enabled and still have about 400 ms
in the cpu meter left

more threads don’t help much and if I try using 13 or 14 threads it starts crackling.

when I play the patch at 41000Hz with 10 threads activated I have about 700 ms left and
with the WASAPI driver I can go down to 64 (1.5ms) ,
this is really good news imho.

I don’t need to change the graphics settings at all, it’s running fine at 90fps and doesn’t change the performance when I change the setting.

@JimT , thank you for your work :+1:

(Jim T) #59

that’s awesome. I’ve also got 8 cores/16 threads and I’ve never found any benefit in any CPU intensive workload in going above core count. I’m sure hyperthreading isn’t actually useless, but I’ve never found a use for it.

glad it’s working for you. I don’t think FPS limiting is going to be useful for you, multi threading is for the higher end machines, FPS limiting seems to be the lower end … and macbooks.

seriously, I have a quad core MacBook and have to FPS limit to play this conversation’s sample patch, even though it’s fine to play on a single thread. something else is going on here I think.

(Joebentley10) #60

I haven’t got the chance to properly try this yet, however it might be worth making a thread just for this fork rather than this one. Excellent work by the way!

PS Andrew does not seem thrilled so maybe we keep it down a bit…