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CPU variable utilization
Old 19th April 2018
  #1
Gear Nut
 

CPU variable utilization

I post here because DP is my main DAW but honestly I don't know if managing DP is the solution of this strange behavior.

This is a copy from another forum where I cannot find help and the "study" was started 10 days ago that I resume in 2 parts.

First tests (april 9):

I’m in testing my new hackintosh i7 8700K High Sierra 10.3.3 DP 9.51.

My test template is an 18 instances of Kontakt (many with keyswitches) with Berlin woodwinds/brass/percussions and LASS for strings (KS+divisi patches).

I have load a MIDI file of 4th mouvement of Beethoven’s symphony 7.

48 khz, 24 bit.

At 256 buffer size no problems at all, all is played without problem and in the busy passages the cpu meter (processing bar) it’s at 40-50%

At 128 buffer size I have 70-100% with some warnings and few audio artefacts.

At 64 buffer size I have 90-100% (the processing meter is almost all time red) with a lot of warnings and a lot of audio artefacts.

Ok, that’s normal I think, but I have see that often the cpu utilization it’s variable with the same buffer in differents reboots of the system and in differents days of test.
For example right now I have played at 128 buffer with no warnings or artefacts (but the cpu meter processing become red in moments).

And, a very surprising thing, yesterday evening after a reboot I can play at 64 buffer with very little cpu utilization, like 45-50% max, no warning at all and no problems with artefacts!

So I go to sleep very happy… this morning the situation has returned like before.

Ok, I am testing overclock too with differents setups in BIOS: 4.7, 4.8 and 4.9 ghz and in general I have some improvements but nothing amazing, so yestrday I think it’s for this the 64 buffer miracle. But no, because yesterday I have try the cpu at stock clock too and the miracle of 64 buffer was still there…

This morning the “magic moment” was passed and all it’s return to “normality”.
It’s all day that I search to reproduce the miracle with no luck.

I have think that was because in a moment yesterday I have open all the strings instances and set to work in realtime (no pre-gen mode), but with no gain in performance so I set up again in pre-gen mode.
So today I have do the same but nothing relevant has change.

1) I’ts normal that the cpu utilization change at the same buffer in different moments,system reboots and days?

2) What happen yesterday with the “64 buffer miracle”?

Second part (today):

Today I have try more tests and the wired thing happen again and this time on "same boot".

First I try my Beethoven test at CPU stock (3.7 / turbo 4.3) and at 64 buffer size was very bad, lot of warnings and audio artefacts.
I reboot with cpu overclocked at 4.7 ghz and give a try to at 64 buffer size and still very bad.
So I try with Logic Pro X and was a little better, but some artefacts was there.
So I try again with Digital Performer without reboot and suddenly all runs very well, no warnings at all and no artefacts and the CPU meter was very low :shock:

So I try with 32 buffer size and still play very well and also with 16 buffer size was very good!!!
All is playing perfect, like if I have another machine

I have made a screenshot that show that DP was playing at 16 buffer size and the CPU meter show that the CPU have no problems at all (with also Intel Power Gadget that I use for monitor CPU speed and temperatures):



How this can be happen?

I have rebooted the machine at CPU stock speed again and… play quite well at buffer 16, no warnings only a few artefacts.
At buffer 32 all is very good and the CPU meter is similar with the screenshot.

So it appears that this very strange behavior of very different cpu performance (128/64 to 16 buffer size it’s VERY different) it’s not related to CPU speed but is done by something else that I really cannot understand what can be.

Any ideas?
I will like, obviously understand the thing for maybe optimize and have control of better performances that now is sure this machine can do.

When the 32 buffer was playing well, I have made some little changes in midi tracks like record keyswitches and suddenly the situation as returned than usual, even if I set at 64 buffer size now I have warnings and artefacts.

That's real mystery for me...
Old 22nd April 2018
  #2
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musicman691's Avatar
The mystery for me is why, if things are okay at 256, do you feel the need to go lower, especially if you're not playing in note lines? If this is just mixing & tinkering around leave it at 256 and you'll be okay. Are you running the second release of DP9.51? There was a second release of that same revision number. Maybe give DP9.02 a try where it's much easier for things to run in realtime than having to keep the plugin guis open and a mini-menu item checked.
Old 22nd April 2018
  #3
Gear Addict
 

Hi

Could be a pregen factor ?
I guess pregen need little time (cpu load) to generate the processed audio, so depending of setup it may vary...
Also IIRC instance opened (window) play real-time, so your performance will vary depending of your opened VI windows.
Did you try setting pregen ON, fresh reboot, then re-open DP and project with all VI windows closed ?
Just some ideas...

Best
Zam
Old 22nd April 2018
  #4
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musicman691's Avatar
Quote:
Originally Posted by zamproject View Post
Hi

Could be a pregen factor ?
I guess pregen need little time (cpu load) to generate the processed audio, so depending of setup it may vary...
Also IIRC instance opened (window) play real-time, so your performance will vary depending of your opened VI windows.
Did you try setting pregen ON, fresh reboot, then re-open DP and project with all VI windows closed ?
Just some ideas...

Best
Zam
This is one of those times where the performance metering window put in by MOTU in the later revision of DP helps as it'll tell you what's realtime and what's in pregen.

But again why work at such low values of samples when higher values work okay?
Old 22nd April 2018
  #5
Gear Addict
 

Quote:
Originally Posted by musicman691 View Post
But again why work at such low values of samples when higher values work okay?
I can't reply to what OP have in mind about this
Depending of situation, which here seem playback only, I may agree with you !
Best
Zam
Old 23rd April 2018
  #6
Gear Nut
 

Quote:
Originally Posted by musicman691 View Post
The mystery for me is why, if things are okay at 256, do you feel the need to go lower, especially if you're not playing in note lines?
I don't fell the "need" to go lower, at 256 but also at 128 (that is good with small/medium projects) I'm very happy because the low latency midi/audio.
I only want understand the potential of this machine and if I can work at 16/32/64 buffer why not.

Sorry but my english is quite bad... what means "playing in notes lines"?

Quote:
If this is just mixing & tinkering around leave it at 256 and you'll be okay.
I mix very rarely and only for quick mockups, I compose and orchestrate so the use is midi-audio for medium-bigs VI templates.

Quote:
Are you running the second release of DP9.51? There was a second release of that same revision number.
This is new for me. I have installed DP 9.51 at the end of february from CD boxed and update online.
The version is the 9.51 74138. I have just ckecked for updates from DP>help>check updates but no new avalaible.

Quote:
Maybe give DP9.02 a try where it's much easier for things to run in realtime than having to keep the plugin guis open and a mini-menu item checked.
Where I can find 9.02?

I know that the default is that all run in pre-gen mode and if you want run in real time some VI you must open the VI window and check the mini menu, Right?

If so I have done this tests but nothing relevant changes.
Old 23rd April 2018
  #7
Gear Nut
 

Quote:
Originally Posted by zamproject View Post
Hi

Could be a pregen factor ?
I guess pregen need little time (cpu load) to generate the processed audio, so depending of setup it may vary...
Also IIRC instance opened (window) play real-time, so your performance will vary depending of your opened VI windows.
Did you try setting pregen ON, fresh reboot, then re-open DP and project with all VI windows closed ?
Just some ideas...

Best
Zam
Thanks for the ideas, but I have try with and without pregen and there are differences but not so big like the "mystery buffer"

In pre-gen all run better but nothing compare to the strange behavior of buffers. 256/128 to 16 is huge!
Old 23rd April 2018
  #8
Gear Nut
 

Update

The “variability” still happen…

Today all was as “usual”, 64 buffer CPU stock and overclocked at 4.7-4.8 not work well.

After some more keyswitch record at 128 no changes so I have try again at 64 just in case… and it works! Works well.
At 16 today work bad.

Can be the springtime?
Old 23rd April 2018
  #9
Lives for gear
 
musicman691's Avatar
Quote:
Originally Posted by johannes2510 View Post
I don't fell the "need" to go lower, at 256 but also at 128 (that is good with small/medium projects) I'm very happy because the low latency midi/audio.
I only want understand the potential of this machine and if I can work at 16/32/64 buffer why not.

Sorry but my english is quite bad... what means "playing in notes lines"?


I mix very rarely and only for quick mockups, I compose and orchestrate so the use is midi-audio for medium-bigs VI templates.


This is new for me. I have installed DP 9.51 at the end of february from CD boxed and update online.
The version is the 9.51 74138. I have just ckecked for updates from DP>help>check updates but no new avalaible.


Where I can find 9.02?

I know that the default is that all run in pre-gen mode and if you want run in real time some VI you must open the VI window and check the mini menu, Right?

If so I have done this tests but nothing relevant changes.
So this was pretty much an exercise then right? Unless you're a drummer you're not going to really need 64 or lower.

'Playing in note lines' means just that - you're playing in the notes from a MIDI keyboard. I'm assuming you're using a MIDI keyboard to enter notes. If not please say so.

I used the word 'mix' to differentiate from actively recording something. Once you have notes entered there's no need to run at low samples.

I didn't know MOTU was still sending out boxed disks with the program. The version you have is the latest one but there was an initial release of 9.51 that had some issues and MOTU released an updated version - you had to look at the build number.

You might be able to get 9.02 from MOTU or maybe some nice person can send it to you. I don't have DropBox anymore so can't help there.

Yes the default for 9.51 is things run in pre-gen mode unless you do certain things mentioned in the manual. If you run your vi's inside VEPro then all those run in realtime mode. There is no more global turn-off of pre-gen in DP sadly.
Old 23rd April 2018
  #10
Gear Nut
 

Quote:
Originally Posted by musicman691 View Post
So this was pretty much an exercise then right? Unless you're a drummer you're not going to really need 64 or lower.
Yes and no, because I have a classical formation (classic guitar) so I am quite sensitive about latency, 64 is better but 128 it’s ok for me.

Quote:

'Playing in note lines' means just that - you're playing in the notes from a MIDI keyboard. I'm assuming you're using a MIDI keyboard to enter notes. If not please say so.
Yes it’s what I do the most, playing in real time and record with a midi keyboard.


Quote:
I used the word 'mix' to differentiate from actively recording something. Once you have notes entered there's no need to run at low samples.
Yes I know that.


Quote:
I didn't know MOTU was still sending out boxed disks with the program. The version you have is the latest one but there was an initial release of 9.51 that had some issues and MOTU released an updated version - you had to look at the build number.

You might be able to get 9.02 from MOTU or maybe some nice person can send it to you
Ok thanks.

Quote:
Yes the default for 9.51 is things run in pre-gen mode unless you do certain things mentioned in the manual. If you run your vi's inside VEPro then all those run in realtime mode. There is no more global turn-off of pre-gen in DP sadly.
I can’t understand the reason why MOTU has put off this function…
Old 23rd April 2018
  #11
Gear Nut
 

@ musicman691

It's long time that I have not opportunity to work with modern hardware so with softwares updates.
It's still possible to have two or more versions of DP installed in the same drive/OS or I must do something for not erase the actual version?

And why precisely 9.02?

Ok, I'm downloading from MOTU 9.02 but 10.13 is not mentioned as a OS supported for this version.
Old 23rd April 2018
  #12
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musicman691's Avatar
Quote:
Originally Posted by johannes2510 View Post
@ musicman691

It's long time that I have not opportunity to work with modern hardware so with softwares updates.
It's still possible to have two or more versions of DP installed in the same drive/OS or I must do something for not erase the actual version?

And why precisely 9.02?

Ok, I'm downloading from MOTU 9.02 but 10.13 is not mentioned as a OS supported for this version.
First: to have more than one version of DP on the same partition rename the first one to whatever you want before installing the second one. Right now I have on OSX 10.10.5 DP9.02, DP9.50 and DP9.51r2.

Why 9.02? Because that's the last DP version to give you the baility to globally turn off pregen in the preferences.

As far a 9.02 mentioned as not being supported in OSX 10.13 what you can do is what I mentioned above about changing the name of your existing DP install and then install 9.02 and see how it runs. The alternative is you learn to work with higher buffer settings that's all.
Old 24th April 2018
  #13
Here for the gear
Hey guys I have created this SOUND ENGINEER SURVEY for my university research project - It's very short, thanks!

Sound Engineer Survey
Old 24th April 2018
  #14
Gear Nut
 

DP 9.02 works worst with and without pre-gen mode but that make not remarkable difference. Maby when is on it's a little better but really little.

Today 9.51 at 64 buffer work very well but at 16 still bad.

In search of ideas of what can happen with the "16 buffer miracle"... but I fell that's is springtime

Thanks for the suggestions.
Old 25th April 2018
  #15
Gear Nut
 

I think that I found the trick

I was doing more tests and in a moment the project has no record enable midi tracks and at 16 buffer my test template play well.
So I enable one midi track and the alert appears. Disable and the cpu meter go down again.
Finally I have understand what's the "trigger".

Now, why only record enabling a midi track give so much work to the CPU? I mean that I am not recording, only enabling but the difference that I can see in the cpu meter is around:
16 buffer size
no midi tracks rec enabled: 45-75%
one midi track rec enabled: still always all the time at 90-100% and over (lot of red alerts) and only in a very few and fast moments go down at 60-70%

That seems a lot to me.

Somebody know why in DP enabling a midi track (that play a v-rack) give so much cpu work?

I have try with a midi track+instrument track instead midi track+v-rack, is even worse...

EDIT
New midi track output assigned to "none" no changes at all if rec enabled or not.
Assigned to a v-rack but no midi data in the track the cpu meter rise again.
Old 25th April 2018
  #16
Gear Addict
 

Hello

So you were not strictly in playback mode...
Maybe CPU load is because DP record and buffer armed track.
At audio you can edge edit before and after a punch in/out
Don't know for midi and VI, but for sure this eat audio engine resources especially at 16 buffer ...

Best
Zam
Old 25th April 2018
  #17
Gear Nut
 

Quote:
Originally Posted by zamproject View Post

So you were not strictly in playback mode...
Yes, not strictly...

Quote:
Maybe CPU load is because DP record and buffer armed track.
At audio you can edge edit before and after a punch in/out
Don't know for midi and VI, but for sure this eat audio engine resources especially at 16 buffer ...
Yes I know that in audio there is a buffer before and after a punch in/out but I don't know how works for midi-VI's.

I am looking if there are some settings in preferences for resolve this behavior.

UPDATE:
I have open ALL the 18 Kontakt instances in my Beethoven test template and set to play in real time and was impossible to hear a note clean, even with no midi track enabled.
So Pre-gen mode works very well for CPU work.
Old 25th April 2018
  #18
Gear Addict
 

Quote:
Originally Posted by johannes2510 View Post
Yes, not strictly...
If we knew this at start !

Quote:
Originally Posted by johannes2510 View Post
I am looking if there are some settings in preferences for resolve this behavior.
16 sample is very low... at 44.1 its more or less 1/3ms !!!
I consider this behaviour as an expected "issue"

I think it's time to make music and not loosing this time to "test" a system latency bellow ms range.

Best
Zam
Old 25th April 2018
  #19
Gear Nut
 

Quote:
Originally Posted by zamproject View Post
If we knew this at start !
I agree

Quote:
I consider this behaviour as an expected "issue"
Me too, but when suddenly my system was playig like have the double power I was very surprised. Now I know why.

But to me it seems incredible that only enabling one midi/v-rack track the CPU go crazy.

Quote:
I think it's time to make music and not loosing this time to "test" a system latency bellow ms range.
Brand new machine here... and I love well know my machines and I have wait long time for upgrade... let me play a bit
Old 26th April 2018
  #20
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musicman691's Avatar
Quote:
Originally Posted by zamproject View Post
If we knew this at start !



16 sample is very low... at 44.1 its more or less 1/3ms !!!
I consider this behaviour as an expected "issue"

I think it's time to make music and not loosing this time to "test" a system latency bellow ms range.

Best
Zam
Agreed. Said it before and I'll say it again - there's no reason to work at such low buffers. 64 should be perfectly fine even for drummers who are the pickiest of musicians.
Old 26th April 2018
  #21
Gear Nut
 

I am in test guys because new machine and I like explore the potential of my new machines.
I don't want play/record midi at 16 buffer, no need of that, I am very happy with 64 or 128 that now I know this machine can do well.

I found interesting explore new technologies and I was stuck with a G5 so you can immagine that I have "a little" to experiment of new things.
Old 26th April 2018
  #22
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musicman691's Avatar
Quote:
Originally Posted by johannes2510 View Post
I am in test guys because new machine and I like explore the potential of my new machines.
I don't want play/record midi at 16 buffer, no need of that, I am very happy with 64 or 128 that now I know this machine can do well.

I found interesting explore new technologies and I was stuck with a G5 so you can immagine that I have "a little" to experiment of new things.
G5? That's an oldie for sure but I bet it kept your studio nice and warm

I'm loving my 2012 Mac Pro cheesegrater (3.46 GHz hex core 48 gig ram) that replaced my 27" 3.4GHz quad core i7 iMac with 32 gig ram. Yes it's a step back in cpu models but it does what I need and I can get in and fix/change things without having to perform major surgery. I like being able to do my own repairs.
Old 26th April 2018
  #23
Gear Nut
 

Quote:
Originally Posted by musicman691 View Post
G5? That's an oldie for sure but I bet it kept your studio nice and warm
And noisy

OMG the PSU and fans of G5 was the background of my last 12 years
Topic:
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