Hello, I’m working on a pretty big track with quite a lot of Kontakt instances going on.
My CPU usage is almost always hitting 95% with each playback, which is honestly pretty tiring to deal with.
Is there a way to freeze tracks, or make the performance better?
Raise your soundcards buffer size is your best bet.
Raise your buffer size and pray 
I’ll guess you don’t experience this same problem in other DAWs right? It’s unfortunately a common issue with Renoise.
1-Use FL studio ASIO as an audio driver. Its is more optimized than ASIO4ALL.
2-Raise the buffer size to the maximum in your audio settings.
3-select more CPUs from Options>multicore/ CPU Support.
4-Render Plugin to Instrument in instruments section.
5-Select (Auto suspend Plugin when silent + Can run in multi processor environment) for all plugins individual settings in mixer and disable them for vst instruments.
6-Render individual tracks and recall them as samples with autoseek - on . Sometimes i apply this for drums and FXs with no further processing.
7-Turn off any oversampling on your mixers dsps .
Yep, render stuff. Or better yet, do all your sound design with sample based synthesis and native devices 
Even my biggest projects barely top 40% and I’m on an old computer.
I realize most people don’t want to work this way, and I offer it tongue in cheek, but the CPU efficiency really is pretty great
If I understand correctly, it’d replace the Device Type here, right?
I’m on 16 CPUs (max), but Renoise seems to only be actively using 8. Not sure why
I’ll try the other ones when I wake up!
Sadly this is one of the few times I’m actively programming and using orchestral instruments for a track… 
I would render stuff out when I finalize the programming though! (Maybe I am torturing myself programming an orchestra in Renoise lmfao)
Yes. If you dont have it just install FL studio demo, The driver comes with it.
Select the multi processing for individual plugins in their individual settings
I would like to draw your attention to the fact that the new Kontakt 7 is still full of bugs. Check your Native Access for updates once a week. They are fixing them.
I recommend to turn off the (Auto Suspend) for instruments. It works better with fxs. You can turn it on in the working process if the CPU load is too high, But you need to remove it before rendering.
Alright. What should I do about the multi processor box though? Should I leave it like that?
Yes. Try to playback the most loaded part of your project when this option is on, If it becomes worse - turn off.
Okay, so I tried raising the buffer size, and now there are very noticeable crackles during playback. I tried restarting my PC, but it’s not doing anything helpful…
Something is very clearly bottlenecked here, I wouldn’t change from your Solid State audio driver as I assume it matches your audio interface. How much RAM do you have, Kontakt is a monster for sample library size and if RAM is bottlenecking then your CPU is going to have idle times as RAM/CACHE are saturated potentially. Do you have the correct XMP profile set for your RAM? What CPU do you have? Have you told your computer to operate in Performance mode (i.e. deprioritise background processes) or are you on a balanced/power saving profile? Is your CPU being adequately cooled? Do you have integrated or discrete graphics - might be worth a FPS limit of 30FPS to reduce render demand on the CPU if you’re running integrated. Higher buffers don’t always equate to less run time errors if the scheduling requested of the CPU is jittering or misaligned.
Use send tracks for FX where possible instead of per-channel FX. Bounce what you can manage to bounce to audio.
If all else fails it’s time to perform ritual sacrifice to the CPU gods. Good luck.
CPU temp is hovering around 45C
I’m not sure if I know what an XMP profile is, definitely will look it up.
Desktops do have a performance mode, at least mine does under Windows 11 Pro running a Ryzen 5700G. A pro licence is cheap from a key reseller online just in case thay feature is locked to Pro. Definitely check XMP is set up in BIOS. Given Kontakt is so RAM intensive, I’d wager something is off there - or youve got a lot of Fx going per instance. Just checking if Kontakt allows you to set its internal render resolution, ive got the freebie Reaktor player and Monark - which defaults to a high sample rate which can hurt CPU. Set realtome rendering to draft and offline to best, so your renders sound top quality but you can compose better in real time.
I almost forgot about that moment with gigantic Kontakt libraries. Performance mode can be found in Control Panel in power settings. Sometimes its called (High performance) or (Ultra Performance). I think that the crackles are caused because of the huge load on RAM and CPU missing processed samples, as you mentioned.
For me it much help to lowers the Soundcards samplerate. On 24 bits 192.0000 hz, i have nearly 98 % cpu usage with some playback stottering. When i reduce the samplerate to 44.100 hz, in the Realtek HD audio software, i am at 16 % CPU usage.
happy tracking 
Absolutely nothing wrong with your machine, it should be able to do the job just fine. XMP profiles are standard manufacturers settings that enable faster RAM clock speeds. Renoise can be a hog sometimes, its really poorly optimized when it comes to resource usage, no other place on earth people would be suggesting that enabling XMP profiles in your 32GB ram is essential to run a bunch of Kontakt instances (LOL). People here gave really useful tips but if you really want to stick with Renoise for this gig it would probably be better to use instruments (there’s a bunch of decent free orchestral instruments out there or you could sample your own Kontakt libraries) and other stock devices (like Zensphere mentioned).
