# Macs Compared: LPX Stress Test



## PeterBaumann (Aug 29, 2020)

I'm having a bit of a re-shuffle at the studio and had assumed that my iMac Late 2014 with its 4GHz i7 Processor was still better for composing than my 2018 MacBook Pro 15" 2.8GHz i7, but I've been running a LPX stress test I found on online and am getting significantly better performance on the MBP. Results below.

*iMac* *5k* Late 2014, 4GHz i7 32GB RAM - *51 Tracks stably* for 1 min+
*MacBook Pro 15"* 2018, 2.8GHz i7 32GB RAM - *73 Tracks stably* for 1 min+

I run my template at 1024 buffer size and that latency is perfectly workable for my purposes. Other settings used for the test are:

Processing Threads: Auto
Process Buffer Range: Large
Multithreading: Playback & Live
Summing: High Precision 64 Bit
Rewire: Off
With the recent release of the new iMacs I've been keeping a close eye on performance. Can anyone with a newer iMac/new Mac Pros update with the kind of results they get with the above settings?

Link to Logic Test Project


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## robh (Aug 31, 2020)

Sure.
Mac Pro 7,1
12-core
48GB RAM

128 buffer size.

About 220 tracks.

Rob


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## Symfoniq (Aug 31, 2020)

Interesting question.

I used the OP's exact settings, although for this particular test, there was no difference between a 128 and 1024 buffer on my machine.

Mac Pro 7,1
16-core
192 GB RAM
128 buffer

310 tracks plays fine.
320 tracks results in system overload.


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## PeterBaumann (Sep 1, 2020)

Gosh, that's quite an improvement. Mac Pro 7,1 - those are the newer 'cheese grater' ones right?

Do either of you use VEPro? What kind of track count are you managing with Kontakt/Play libraries running in a session?



Symfoniq said:


> I used the OP's exact settings, although for this particular test, there was no difference between a 128 and 1024 buffer on my machine.



I also found that the buffer size didn't seem to make much difference for this test. When using VEPro & orchestral Kontakt/Play libraries though, I usually get crackles and pops for anything less than 1024 buffer.


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## Tatu (Sep 1, 2020)

iMac Pro, 3.2/8-core, 32Gb of RAM starts to choke at 170 tracks.


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## Symfoniq (Sep 1, 2020)

PeterBaumann said:


> Gosh, that's quite an improvement. Mac Pro 7,1 - those are the newer 'cheese grater' ones right?
> 
> Do either of you use VEPro? What kind of track count are you managing with Kontakt/Play libraries running in a session?
> 
> ...



Yes, the Mac Pro 7,1 is the 2019 cheese grater.

I own VE Pro but rarely use it these days.


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## ptram (Sep 1, 2020)

Mac Pro 6,1 (2013)
12-core, 2.7GHz
64GB RAM

128 buffer size

115 tracks


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## brek (Sep 1, 2020)

PeterBaumann said:


> I also found that the buffer size didn't seem to make much difference for this test. When using VEPro & orchestral Kontakt/Play libraries though, I usually get crackles and pops for anything less than 1024 buffer.



I'm a Cubase user, but was running some tests in Logic and noticed very little difference in performance at 32 or 1024 buffer settings (occasional pops and clicks at lower buffer settings, of course). Even quickly testing the stress test at the link, the failure point between the two buffer settings was 80 tracks vs 85 tracks. In a thrown together Cubase test, the track count doubled going from a buffer of 64 to 256 (which closer matches my real-world experience). Caveats about small sample size and lack of scientific rigor apply here.


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## PeterBaumann (Sep 1, 2020)

brek said:


> I'm a Cubase user, but was running some tests in Logic and noticed very little difference in performance at 32 or 1024 buffer settings (occasional pops and clicks at lower buffer settings, of course). Even quickly testing the stress test at the link, the failure point between the two buffer settings was 80 tracks vs 85 tracks. In a thrown together Cubase test, the track count doubled going from a buffer of 64 to 256 (which closer matches my real-world experience). Caveats about small sample size and lack of scientific rigor apply here.



Thanks for running those tests. What are your system specs?


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## Kent (Sep 1, 2020)

on my Hackintosh (probably most similar to the current top iMac) there is no difference I can discern between running at 1024 or 32 sample buffer size. 

RAM effect on this benchmark is basically negligible, too.

If anything, this benchmark tests your CPU and audio driver combo. Thus:

i9 10900k @ 4.8 GHz & RME Fireface UFX+ (Thunderbolt) - stable at 193 Tracks


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## Kent (Sep 1, 2020)

kmaster said:


> on my Hackintosh (probably most similar to the current top iMac) there is no difference I can discern between running at 1024 or 32 sample buffer size.
> 
> RAM effect on this benchmark is basically negligible, too.
> 
> ...


I'm not sure how useful it is for gauging efficiency at using 3rd-party libraries like those found in Kontakt, and/or from hosting things in VEP. For example, Large Process Buffer Range is good here, but I find I get better performance at Small when using VEP. So this test really seems to show what your limits are when producing native Logic-only things—helpful to know, but not a 1:1 correspondence with real-world use.


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## PeterBaumann (Sep 1, 2020)

kmaster said:


> I'm not sure how useful it is for gauging efficiency at using 3rd-party libraries like those found in Kontakt, and/or from hosting things in VEP. For example, Large Process Buffer Range is good here, but I find I get better performance at Small when using VEP. So this test really seems to show what your limits are when producing native Logic-only things—helpful to know, but not a 1:1 correspondence with real-world use.




True - the other consideration is that my (more powerful) MacBook Pro is running at max fans nearly all the time when working. It is significantly more noisy than the iMac it is potentially replacing.


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## JohnG (Sep 1, 2020)

kmaster said:


> I'm not sure how useful it is for gauging efficiency at using 3rd-party libraries like those found in Kontakt, and/or from hosting things in VEP.



Yes -- it's an interesting exercise but remains sort of an academic "noodle," because of @kmaster 's point, and also running at 1024 as a buffer. I don't know how anyone can work with that buffer.

Still, thanks for starting the thread, @PeterBaumann and raising the issue. I'm not sure what other test anyone can really run because of idiosyncrasies in setups and libraries. I have a USB hub with 10 extra inputs and most of them are full (drives, printers, Bluetooth receiver for a mouse -- the usual). So I'm sure anyone looking at my setup (or "yours") would say, "you can't expect anyone else would the same result with all that clutter." 

My guess, though, is that many people have a lot of clutter.

Consequently, short of spending $10k just to see, it's daunting to conceive a reliable experiment that would clarify whether it's worth updating one's Mac!


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## IFM (Sep 1, 2020)

The reason you are all getting the same/similar readings on different buffer sizes is because of Logic's dual buffer. The buffer size setting only matters on armed (live) tracks. All other tracks are processed at the (small, medium, large) setting. I think medium is 2048 (might be mistaken on the exact # as it's not published).


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## Kent (Sep 1, 2020)

IFM said:


> The reason you are all getting the same/similar readings on different buffer sizes is because of Logic's dual buffer. The buffer size setting only matters on armed (live) tracks. All other tracks are processed at the (small, medium, large) setting. I think medium is 2048 (might be mistaken on the exact # as it's not published).


Right, which is why it doesn't matter for this benchmark—and also why this benchmark doesn't tell the full story


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## PeterBaumann (Sep 1, 2020)

Would doing a similar test with the basic kontakt library loaded be a better test of real-world performance, or still fairly irrelevant?


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## Kent (Sep 1, 2020)

PeterBaumann said:


> Would doing a similar test with the basic kontakt library loaded be a better test of real-world performance, or still fairly irrelevant?


It’s one thing to play things as if mixing, but IMO the real bottleneck is real-time performance ability. How many “pre-mixed” tracks can you run while recording a heavy MIDI instrument?
The issue with this is that we all work differently, and even if we have the same hardware and software often value different workflows, so even finding a meaningful metric there is difficult if not impossible.


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## Kent (Sep 1, 2020)

And I wouldn't say it's irrelevant, just that it's not very relevant, although probably the closest thing to truly relevant of any similar benchmark. It's worth knowing what the "limits" of your system are.


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## Virtuoso (Sep 1, 2020)

Symfoniq said:


> I used the OP's exact settings, although for this particular test, there was no difference between a 128 and 1024 buffer on my machine.
> 
> Mac Pro 7,1
> 16-core
> ...


Damn! I have the same CPU but double the memory and mine craps out at 298 tracks.

Mac Pro 7,1
16-core
384 GB RAM
128 buffer

297 tracks


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## robh (Sep 1, 2020)

PeterBaumann said:


> Do either of you use VEPro? What kind of track count are you managing with Kontakt/Play libraries running in a session?


I use VE Pro and as a comparison, a full orchestra piece I wrote would choke, sputter and get System Overloads on my Mac Pro 5,1 3.33 6-core. This new machine barely touched 25% in any thread in Logic's performance monitor.

Rob


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## Symfoniq (Sep 1, 2020)

Virtuoso said:


> Damn! I have the same CPU but double the memory and mine craps out at 298 tracks.
> 
> Mac Pro 7,1
> 16-core
> ...



Interesting! What audio interface do you use? I’m using RME via USB. Latest Logic Pro X.


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## JamieLang (Sep 1, 2020)

brek said:


> I'm a Cubase user, but was running some tests in Logic and noticed very little difference in performance at 32 or 1024 buffer settings (occasional pops and clicks at lower buffer settings, of course).



Apple to orange tools.  They buffer totally differently. The reason OP sees little difference in the PLAYBACK performance between 32 and 1024 is because that buffer setting in Logic doesn't AFFECT the playback engine playing back all these VI tracks. Only the channel selected in the main page (and whatever auxes are in it's signal flow path). If you set up a (no output) dummy track to rest your "arrange window focus" on, it theoretically should show NO difference because nothing changes when you move that buffer.

As you were. Didn't want to derail...just hate to leave that hanging how these apps buffer differently...


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## Virtuoso (Sep 2, 2020)

Symfoniq said:


> Interesting! What audio interface do you use? I’m using RME via USB. Latest Logic Pro X.


A couple of UAD Apollo x8s over Thunderbolt. I am running at 6k though - maybe that taxes the CPU more heavily? Activity Monitor showed the CPU load at 86% at the point where Logic could take no more tracks.


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## PeterBaumann (Sep 2, 2020)

New iMacs:

3.8GHz i7 8-core, 32GB RAM - 123 Tracks
3.6GHz i9 10-core, 64GB RAM - 131 Tracks


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## cowudders (Sep 24, 2020)

PeterBaumann said:


> New iMacs:
> 
> 3.8GHz i7 8-core, 32GB RAM - 123 Tracks
> 3.6GHz i9 10-core, 64GB RAM - 131 Tracks



Thought about exchanging my Mac Pro 5,1 cheese 12 core 3,46Ghz for the new imac 2020 i7 which seems to be at around 30% faster on geekbench5 f..e, but i'm totally unsure now. i get 115 tracks on the 'newlogicbenchmark' easily and 23 tracks on the divatest. both with procbuffer medium, 128 samples buffer with an RME raydat running on Mojave. this machine just hums along...

can somebody confirm the 123 tracks on the new imac i7 8-core?


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## gst98 (Sep 24, 2020)

cowudders said:


> can somebody confirm the 123 tracks on the new imac i7 8-core?



I just got the 10 core and was getting high 140s with this test.

edit: I should have mentioned I've got 72gb of RAM in it currently.


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