Anyone else using Ardour 8.12 on a Mac (Mine is a Mac Studio with OS 15.n) and getting GUI framerate slowdown and high CPU on only a few instrument plugins? I have a session with only 4 instrument plugins and the GUI gets really slow, making metering unusable and CPU power reading 250%. Audio seems fine, it’s just the GUI and high CPU useage. The ‘equivalent’ in Logic (Yeah I know it’s not really a comparison) gives me smooth graphics and a CPU rate of around 50%.
1 Like
What, specifically, are the plugins that cause this?
I would like to know.
Try disabling all but the first one, then note the CPU usage after several seconds.
Then disable that one, and enable just the next plugin and note the CPU usage, etc., until you narrow it down.
Alternatively, open Window > Plugin DSP Load 
2 Likes
I thought someone would ask that! I’ll need to spark it up again to check but there were an instance or two of Kontakt 8 and I can’t remember the rest. The fact that I can’t remember says it all - in Logic I’m not concerned as it just gets on with it.
One thing to know about Ardour is that we deliberately don’t play games to try to keep DSP load low at “special times”. We aim for constant DSP load no matter what is happening.
Logic might manage to do that too, but there are DAWs out there that, for example, disable plugins under specific conditions and then have the DSP load spike under others.
1 Like
Tried that and a couple of them are indeed DSP-heavy but even so, only 4 tracks and a Mac Studio is being caned for the want of 4 instruments. Sorry to keep making the comparison but Logic does this better. 50% max for more instantiations of the same plugins makes me wonder if the Mac version of Ardour isn’t as optimised as it says on the tin.
It’s not a thing that we’ve spent lot of effort trying to optimize. The comparison with Logic in particular is less interesting to us, because we know that Apple plays some internal games, using OS APIs that are not documented. But we also know that other DAWs sometimes do better than Ardour.
It’s as optimized as its going to be for a while. If that doesn’t work for you, the good news is: you still have Logic!
We’ve also found that the measurement of “DSP load” itself varies across different DAWs. Ardour is more or less the only one where you can go and read precisely what we measure. A few years we did some detailed investigation comparing Reaper and Ardour, and even though the displayed numbers were different, the actual DSP load was essentially identical in both.
Finally, another trick that quite a few DAWs have started to use is to differentiate between “live” tracks and non-live ones. The non-live ones use much bigger buffer sizes than the live ones, which means that response to knob twiddling etc. is a bit more latent. While we understand that this does provide the experience of lower DSP load, it’s not an engineering road we want to go down.
1 Like
Thanks for the explanation. I appreciate it. I’m sure that Ardour can process any number of MIDI inst. tracks but my gripe is with the GUI getting so ‘low framerate’. My Mac Studio can handle the workload of course but from a display point of view it’s less than optimal.
Can you check that Preferences > Appearance > Quirks > Use macOS to determine GUI redraw areas is disabled?
On my macbook m3, ardour easily gets to 80 fps when needed, and settles down at around 50-60 fps.
1 Like
Ah, thanks. I’ll check tomorrow. That could be it.
Actually, probably not
Ah.I won’t get my hopes up too much then!
Thanks. I saw that earlier when I was searching around on the subject.
Thing is the effect you’re seeing there in a plugin, I’m seeing on the whole Ardour GUI. I must have something set wrongly somewhere …
@paul O_____O
Thank you so much!
Ha, you just totally, inadvertently solved my own plugin GUI issues.
This one, as @jean-emmanuel also mentioned:
Voxengo Plugin GUIs Lagging Badly on macOS (Mojave)
→ I had Use macOS to determine GUI redraw areas turned ON, and once I turned it OFF, all the graphics lagging was fixed! 
So yeah, @PaulN, please do try the same.
Turn that setting off and try the DAW again.
…
It does sound like it might be a mixed-bag for you though.
Like, maybe the GUI lagging will be helped, but not the cpu usage?
-J
That sounds very promising, thanks. I’ll try it later today.
1 Like
Well, I tried switching off:
‘Use visibility information provided by your Window Manager/Desktop’ for kicks just in case,
and
Use macOS to determine GUI redraw areas’
and neither made any difference I’m afraid. Now I’m stumped.
To answer the question of what plugins I was using they are:
Korg M1
Korg Wavestation
(Arturia’s) Analog Lab V
Hybrid (Air)
Kontakt 8/Ethereal Earth
Kontakt 8/Ethereal Earth (different patch)
And H-Reverb (Waves)
I’ve since reinstated '‘Use visibility information provided by your Window Manager/Desktop’ as bits of windows were disappearing until I mouse-hovered on the elements that were missing.