divergent ssd speed test results

[zephonic]

This may not be very critical, but inquisitive minds want to know; I have an Samsung 850EVO (500GB) on an OWC Accelsior S PCIe card in my '09 quad.

Trim Enabler's benchmark shows:

BlackMagicDesign's Disk Speed Test shows:

330MB/s or 524MB/s read speeds seems like an unusually large deviation, or are they measuring two different things? If not, who is right and who is wrong?

 

[Weaselboy]

I know BlackMagic uses incompressible data for its test, so that might make it read differently. Maybe try AJA for a third opinion.

 

[jimj740]

In general, it is very difficult to characterize device performance on OSX, since it is practically impossible to bypass the buffer cache. The blackmagic benchmark, in my personal experience, is more susceptible than most other benchmarks to caching by OS X.

This does NOT mean that blackmagic is a bad benchmark - it's purpose is to demonstrate the performance of the system for different video rates, and the system includes both filesystem and the buffer cache.

The root cause of your confusion is that you are trying to characterize device performance with a tool designed to characterize system performance.

 

[MrAverigeUser]

I had exactly the same problem 10 days ago.

look here and also at following postings:

https://forums.macrumors.com/thread...-pro-ssd-thread.1508877/page-51#post-22470709


I have a response of Oscar, the developer of TrimEnabler at Cindori about the irritating READ-Performance test results.
This is indeed caused by a bug:

https://www.cindori.org/forums/topic/bug-in-performance-test-of-trim-enabler-3-4-2-2/


In my case (840EVO) , AJA and BLackmagic results are constantly nearly the same and performance as predicted and specified by Samsung. There is nothing wrong with the 850 Evo, it´s just a little bug of coconut battery, nothing else.
But better install and enable TrimEnabler.

 

[zephonic]

Thanks for sharing that. But the link appears to be broken?

 

[MrAverigeUser]

Thanks for sharing that. But the link appears to be broken?

oups..., this link was indeed broken. edited the broken link in my postings..

here is the correct one:

https://www.cindori.org/forums/topic/bug-in-performance-test-of-trim-enabler-3-4-2-2/