CPU spiking & plugins... why?

[auptown]

OK, this is weird. I have a project with 3 stereo audio tracks, with sporadic dialog sections a second or two long. All three have a send going to another audio track with a reverb plugin. The three tracks also have MOTU gates on them.

Here's what happens: when the audio kicks in for a track, after a small silence, I get a CPU spike. If I have the gates on (not disabled), I get the spikes a lot more. Perfectly repeatable, once it's happening it happens every time at the same places.

So I watch the CPU meter and I see spike, spike, spike.

Lot's of things change it, like using Rayspace or Arts Acoustic it happens more, and if I disable the gates it happens less. But it never goes away?

What is this?? I'm running at 256 buffers, and I've tried some other settings changes but nothing is making this go away.

[XYZ]

There are plenty of posts and plenty of reasons for these. However, a friend of mine just spent a whole boatload of time trying to get his machine to not spike. He tried clean installs, replacing memory, etc.

What eventually worked for him was to shut off dashboard. There is a little utility that will turn it on and off for you.

I'd try this as one of my first ideas, since it is so easy to try. Let us know what you come up with.

[David Polich]

FWIW, I've learned not to get too upset about spikes. I get one at least once a session, if not three times a session, about every three days or so. Big projects, small projects, lots of plugs, no plugs, doesn't seem to make a difference.

If the processor spikes and it doesn't ruin any audio, then I kind of ignore it.
If the processor gets "stuck" in the red, then I know a crash is imminent and I immediately mute my mixing board, because crashes can often be accompanied by that screeching ear-shattering digital noise explosion coming through my audio interface. Not a pleasant experience.

I do notice that I see more spikes anytime I'm under 512 buffer size. At 256 they start to occur more often, at 128 even more often, at 64 - geez, I don't think I've ever cranked them down that far. I don't even know if 64 is an option for buffer size in DP.

[auptown]

XY -- thanks for the idea, I have had dashboard disabled on that machine for a while now.

Normally I wouldn't worry much, but it's just that these spikes happen exactly when some sound gets sent to a reverb plugin, and it's repeatable. There has to be *something* going on here.

Also, I have trouble with the reverb effect itself. Some sound bites get no reverb, sometimes the reverb tail cuts off too soon. And this is even after I merge soundbites in the whole track.

Odd, very odd.

[XYZ]

What kind of reverb is it?

[Frodo]

Things I've found that cause spikes:

1. Busy firewire busses-- Solution: split up data paths across independent busses, especially if a FW audio interface is involved. Run as much data as possible to/from SATA.

2. Running effects in real time-- Solution: pre-render effects

3. Low buffers- Solution: raise buffers

4. Not enough RAM for the tasks at hand- Solution: add more RAM if possible or try to economize on CPU-hungry plugins like reverbs-- submix to aux's whenever possible and use independent instances of reverbs only when absolutely necessary-- freeze tracks whenever possible, especially if lost of convolution reverbs are in use.

5. Virtual Memory not having enough time to rewrite file references or having too much data at once to refresh file references. --Solution: Adjust DP's Work Quanta. This governs the frequency at which MAS does its calculations. Raising the number to above 100ms might help--- Solution: Check any VI's preferences and set its disk usage/streaming higher.

6. Dropped voices-- Solution: make sure you have enough stereo busses available in your Bundles, and be aware that there are voice limits based upon the amount of RAM you have installed. DP will drop voices if there is not enough memory.

Also, be aware that DP has been known to just spike even on boot. Just opening a project can show the red peak indicator without even hitting play the first time. This might be resolved in DP6, but such spikes are not uncommon in DP5 and earlier.

One unothodox solution that worked on my PPCs: Set host multiplier to 2. This is VERY unorthodox, I know-- but it helped lower CPU spikes. YMMV!!!

[newrigel]

OK, this is weird. I have a project with 3 stereo audio tracks, with sporadic dialog sections a second or two long. All three have a send going to another audio track with a reverb plugin. The three tracks also have MOTU gates on them.

Here's what happens: when the audio kicks in for a track, after a small silence, I get a CPU spike. If I have the gates on (not disabled), I get the spikes a lot more. Perfectly repeatable, once it's happening it happens every time at the same places.

So I watch the CPU meter and I see spike, spike, spike.

Lot's of things change it, like using Rayspace or Arts Acoustic it happens more, and if I disable the gates it happens less. But it never goes away?

What is this?? I'm running at 256 buffers, and I've tried some other settings changes but nothing is making this go away.

Looking @ your sig you have quite a bit happening on that FW buss...
Are you using a PCIe firewire card or just the Mac Pro's?
Does it do it once in a while or is it just with this project? 3 stereo tracks.. this is not good. Unless I'm playing a VI I rarely have my buffers below 1024 anyway so...
My DSP meter is around 10- 15% on a session like this @ most.
I have a LM also and It eats some cycles off the FW bus (and you have a Duende too!) so I just set up a template with the maximum amount of plugs it can handle (32 mono or 16 stereo) and only turn on those tracks that I'm using @ the moment and I don't have too many problems...
But since I set up a ROCK SOLID working template, I haven't had any problems but I'm not a facility where you have to accommodate different clients etc. so.
Also make sure you have on the plugins "always run in realtime" checked. I know my LM acts up big-time unless this is checked on EACH instance used...
Just my 2 cents but I would remove each FW device and see if they are the culprit... Just doing this you may find that one of the FW peripherals are the problem and to take the appropriate measures.

[Spikey Horse]

I doubt this is it, but one more for the road:

- disable all automatic background processing

Actually I remember getting very brief CPU spikes along with hardly noticeable (but still there!) audio glitches from BFD (this was years ago) when bouncing MIDI tracks to audio in real time ... always in the same places too! ... eventually turning off background processing stopped it, so you never know.....

[aletheian-alex]

Here's what happens: when the audio kicks in for a track, after a small silence, I get a CPU spike. If I have the gates on (not disabled), I get the spikes a lot more. Perfectly repeatable, once it's happening it happens every time at the same places.

Yes, i have had that problem since i switched from DP4, and there are a couple lengthy threads about it around the internet. No combination of settings will make it go away. it only happens with certain plugins on silent passages It is absolutely repeatable, so I have had to just work around it and pray that it gets fixed in DP6.

[guitron45]

d. There is a little utility that will turn it on and off for you.

What utility will turn off dashboard. Is it part of the os or a DL app?

Thanks

Ron

[dosuna11]

Try this from Native Inst.

http://www.native-instruments.com/index ... 41&flash=9

[guitron45]

Try this from Native Inst.

http://www.native-instruments.com/index ... 41&flash=9

Thank you for the link but I don't see anything about dashboard in the seven pages that this link leads to. Naturally I did not want to read seven pages of material. But I scanned every page and saw nothing about Dashboard or any link to DL an app. Could you please be more specific? What is the name of the app.

Ron

[Anders Peev]

I had the same problem. I was running my DP projects from an external FW drive and an FW audio interface. After moving the projects to the internal HD the spiking and crasching stopped.

/

A

[Shooshie]

d. There is a little utility that will turn it on and off for you.

What utility will turn off dashboard. Is it part of the os or a DL app?

Thanks

Ron

Go to Versiontracker.com and look for DashOff.


Shooshie

[dosuna11]

Try this from Native Inst.

http://www.native-instruments.com/index ... 41&flash=9

Thank you for the link but I don't see anything about dashboard in the seven pages that this link leads to. Naturally I did not want to read seven pages of material. But I scanned every page and saw nothing about Dashboard or any link to DL an app. Could you please be more specific? What is the name of the app.

Ron

No app., just real good info that I found almost eliminated all my spikes and pops.
Hope it works for you.
D