Live v9.5 performs better WITHOUT Multi-core support!!

[keyman_sam]

Live has been struggling to play a moderate sized project (60 tracks) in my i7 2600K/20GB ram DAW with RME Babyface, which used to run 120+ tracks in Reaper without breaking a sweat at 256 samples. It is notable that this is my first serious project in Live after moving away from Reaper. This project literally has 3 VSTis - 1 omnisphere, 1 Kontakt, 1 EW Play. The rest are audio effects on audio tracks and sends, mostly Live's effects.
Also I've moved the project to a fresh 64-GB SSD to remove disk streaming concerns.

With all the stuttering I tried turning off Multicore support and lo-and-behold it actually got rid of a lot of the audio glitches. THe CPU now runs at 65-70% as opposed to 45% but the performance seems noticeably improved.

What should I gather from this? Is Ableton poorly optimized for multi-core support? Any solution I can try? I've played way bigger projects in Reaper without any glitches, so it can't be the computer. In fact as far as I can remember this is the first time I'm experiencing performance related problems in this computer. HELP!!

[jestermgee]

I'm not a complete expert in this area but as I understand with multi-core usage is your CPU there has 4 processors with 2 "cores" per processor. each track in Live will be designated to a processor/core so if you have lets say omnisphere with all 8 layers running these will all run within a single core (with multi-core enabled) or within a processor (without it enabled).

You have a total CPU power divided up over all this so having too much in a single track can kill things more than spreading it over more tracks.

All 3 of the devices you have listed are monsters and I use all these also. The first thing I have had to learn to do is NOT use too many layers in a single instance. If you use EW for strings for instance, don't load an entire orchestra section into one instance, use 4 instances instead. It helps spread the load.

I haven't used Reaper but from what I hear they have a pretty good system for handling CPU cycles and audio. You never can guarantee any DAW will perform the same for the same elements.

[fishmonkey]

not quite. it is one processor with four cores (quad-core). each of these four physical cores can run two threads, which in total is like having 8 virtual cores.

the thing is having multiple cores means running processes in parallel, which involves a whole lot of extra synchronisation, and audio processing is very unforgiving.

it might be a bug in Live, or it might be related to how the computer is configured.

the comparison between Live and other DAWs comes up all the time, and the bottom line is that it is not reasonable to expect Live to perform on par with an efficient linear DAW. the only valid comparison is with Bitwig Studio.

[zeepster]

If multi-core support = off, does Live still use multiple cores and not virtual cores?

[fishmonkey]

If multi-core support = off, does Live still use multiple cores and not virtual cores?

no, only a single thread is used.

it's pretty easy to test. fire up your system's CPU monitor and create a few processor hungry tracks, and toggle multicore support on and off.

[zeepster]

Ah of course.
Thanks for explaining it.

[borg]

try shuffling tracks. Live in multimode uses one 'processor' per track. With two processors, that would mean putting heavy devices on track 1 and 3 and lighter devices on 2 and 4 will make processor 1 work much harder. Swapping 2 and 3 will even things out. iirc...

[Stromkraft]

try shuffling tracks. Live in multimode uses one 'processor' per track. With two processors, that would mean putting heavy devices on track 1 and 3 and lighter devices on 2 and 4 will make processor 1 work much harder. Swapping 2 and 3 will even things out. iirc...

How do you reckon this to be working? Most songs have 15 to 30 tracks at least. There's no shuffling to be done there, right?

[borg]

well... in the case of two processors:

track 1: plugins consume 45% of CPU 1
track 2: plugins consume 5% of CPU 2
track 3: plugins consume 45% of CPU 1
track 4: plugins consume 10% of CPU 2
this results in a CPU 1 load of 90% and CPU 2 load of 15%

if you move track 2 behind track 3 (so 2 becomes 3, and 3 becomes 2) CPU 1 load becomes 50% and CPU 2 load will be 55%.
something to consider if your hitting ceilings.

[fishmonkey]

well... in the case of two processors:

you make a good point, but it's confusing things a bit using the term 'processors' here. i think what you are talking about is paying attention to which virtual cores are being used, to better spread the load across the physical cores...

[borg]

ah, yes, I realized after posting 'core' would have been more appropriate, or better, correct... my bad

[keyman_sam]

well... in the case of two processors:

track 1: plugins consume 45% of CPU 1
track 2: plugins consume 5% of CPU 2
track 3: plugins consume 45% of CPU 1
track 4: plugins consume 10% of CPU 2
this results in a CPU 1 load of 90% and CPU 2 load of 15%

if you move track 2 behind track 3 (so 2 becomes 3, and 3 becomes 2) CPU 1 load becomes 50% and CPU 2 load will be 55%.
something to consider if your hitting ceilings.

I have core parking disabled and I view my cores in the task manager - I don't see this being the case. The load looks pretty evenly distributed.

[fishmonkey]

With all the stuttering I tried turning off Multicore support and lo-and-behold it actually got rid of a lot of the audio glitches. THe CPU now runs at 65-70% as opposed to 45% but the performance seems noticeably improved.

if you are still getting some glitches running on one core then you cannot infer that it is the multicore support that is causing the problems, merely that running in multicore mode is aggravating the issue, which is not in itself surprising.

[pencilrocket]

when will we get up-to-date multicore support like other &200+ DAWs?

[NoSonic822]

live can only assign one of the 4 cores to a single track....so if you have tons of stuff on one track....and you only have one track in your project, that could actually max it out. then if you have 4 tracks with tons of stuff...it will just be the same but multiplied...but if you have 4 tracks with not much stuff.....compared to a single track with tons of stuff...then you will probably have less cpu usage

so the cpu usage is only as good as the one core can handle...but you can handle 4x that amount because of the 4 cores. but each one is exclusive