Mac Pro RAM Disk Speed Test

VaZ

macrumors regular
Original poster
Aug 31, 2012
132
31
So i'm curious what kind of throughput others get doing a benchmark speed test on their ram disk. I'm using Disk Speed Test and AJA System Test.

Using a MP5,1 with 4x16GB DDR3 ECC 1333MHz ram in Dual-Channel mode i get around 2400MB/sec read and 2100MB/sec writes with about a dozen apps open testing on a 4GB RAM Disk.

Does this seem normal? PCIe NVMe drives seems to reach 3500MB/sec on these units. Is RAM that much slower ?!?

Please post results!
Screen Shot 2019-03-26 at 8.10.17 PM.jpg
 
Last edited:

upandown

macrumors 6502a
Apr 10, 2017
621
450
Pretty crazy to see storage actually catching up to RAM if these tests are accurate.
 
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TobiasT

macrumors member
Jan 24, 2019
33
20
That's your RAM Disk on a fresh boot?
Actually, Chrome was in the background with several tabs (mac rumors, youtube...).

The RAM Disk was created with TmpDisk app.

Pretty crazy to see storage actually catching up to RAM if these tests are accurate.
Well, they might catch up sequential transfer speeds, but RAM is not for sequential transfers.
 

VaZ

macrumors regular
Original poster
Aug 31, 2012
132
31
Geez your speeds are much faster than mine. I also used TmpDisk app. How many sticks do you have in your 6,1? Quad-Channel or something ?!?
 
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TobiasT

macrumors member
Jan 24, 2019
33
20
Geez your speeds are much faster than mine. I also used TmpDisk app. How many sticks do you have in your 6,1? Quad-Channel or something ?!?
MP 6.1 is four-channel, and I have four dimms (standard speeds for MP 6.1).
 

VaZ

macrumors regular
Original poster
Aug 31, 2012
132
31
Very nice!
Maybe thats where my top speed suffers because of the dual-channel config i'm on atm and slower ram clocks
Screen Shot 2019-03-26 at 9.14.43 PM.jpg
 
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TobiasT

macrumors member
Jan 24, 2019
33
20
I am not sure, but I think your cpus are three-channel. So, yes, filling (the right) extra slots should help. I do not think ram clocks are that important. Nowadays, one can buy 4600 Mhz and the speed increment would be much smaller that what the big Mhz number suggests.
 
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kwikdeth

macrumors 65816
Feb 25, 2003
1,038
1,341
Tempe, AZ
Pretty crazy to see storage actually catching up to RAM if these tests are accurate.
you mean storage technology surpassing the speeds of 10 year old DDR3 RAM. I dont think that comparison would hold up if you went head to head on DDR4-2666 vs NVMe. A more suitable comparison would be on the new iMacs or Mac Minis that use DDR4.
 

TobiasT

macrumors member
Jan 24, 2019
33
20
you mean storage technology surpassing the speeds of 10 year old DDR3 RAM. I dont think that comparison would hold up if you went head to head on DDR4-2666 vs NVMe. A more suitable comparison would be on the new iMacs or Mac Minis that use DDR4.
Do you have numbers of DDR4-2666?
 

VaZ

macrumors regular
Original poster
Aug 31, 2012
132
31
Holy Crap that's Fast!
I'm curious what your Mac Pro can achieve with your setup.
 

TobiasT

macrumors member
Jan 24, 2019
33
20
Cool!!

Hackintosh are the best performing macs, except they do not fully support Mac OS.
 

h9826790

macrumors G5
Apr 3, 2014
12,944
5,828
Hong Kong
Cool!!

Hackintosh are the best performing macs, except they do not fully support Mac OS.
Which part not supported?

MacOS seems work better on my Hackintosh than cMP.

e.g. I have full GPU encode / decode support on my Hackintosh in macOS, which my cMP still can do it yet.
Hardware Acc Engine.png

This also make me able to use the Airplay To function.
Screen Shot 2019-03-28 at 06.23.59.png
 

TobiasT

macrumors member
Jan 24, 2019
33
20
The topic is about RAM Drive speed. I want to see more RAM Drive speed.s I do not want to discuss why "perfect-compatibility" hackintoshs use old versions of Mac Os instead of the very last version ;-)
 

h9826790

macrumors G5
Apr 3, 2014
12,944
5,828
Hong Kong
The topic is about RAM Drive speed. I want to see more RAM Drive speed.s I do not want to discuss why "perfect-compatibility" hackintoshs use old versions of Mac Os instead of the very last version ;-)
OK, fine, but it's you to start this topic in this post, that's why I want to know more why you believe this.

Anyway, Hackintosh nowadays can run the latest macOS build (including the up to date beta).

To make it clear, my RAM drive speed was from a Hackintosh because that's exactly DDR4 2666 as per request. And I post that "About This Mac" is to let the other know where this DDR4 2666 result coming from, with which CPU etc. I have no intention to start any discussion if Hackintosh is good or bad in this cMP forum.

Back to the topic, from memory, there was a post about making multiple RAM drive, then RAID them together can improve RAM drive speed. Is there anyone know the exact method to create and RAID the RAM drive for that particular purpose?
 
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Slash-2CPU

macrumors 6502
Dec 14, 2016
304
157
New Orleans, USA
Dual-CPU 5,1 interleaves RAM between the sockets. There's a performance penalty for linear operations.

I wouldn't be surprised if a single-CPU 5,1 with a W3690/X5690 and triple-channel DDR3-1333 is the fastest variant of 5,1 on this test.
 
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