Question Why am I getting impossibly high results on my Samsung 860 EVO SSD?

[inkydink815]

Hey all,

I just got a new SSD fairly recently and the results in Samsung magician seem "a bit" unrealistic (sarcasm). My read AND write speeds are in the range of 2,400-2,600 MB/S. That's near 20 GB/s. This is a SATA 6GB/S drive (my board doesn't even have any other internal storage interface). Why am I getting these results when they are clearly impossible?

 

[Zephyl]

20GB/s? Don't you mean about 2.3GB/s?

 

[hotaru251]

a GB is aroudn 1000 MB.

so as above stated your only at 2.3GB/s(or 2.4 rounded)

 

[JazzyJazzJ]

SPECIFICATIONS

• Form Factor
• 2.5 inch, mSATA, M.2

• Capacity
• 250 GB, 500 GB, 1,000 GB, 2,000 GB, 4,000 GB

• Sequential Read Speed
• Up to 550 MB/sec

• Sequential Write Speed
• Up to 520 MB/sec

Samsung 860 EVO | Consumer SSD | Specs & Features | Samsung Semiconductor Global

860 EVO delivers 2.5-inch, M.2, mSATA form factors and capacities ranging from 250GB to 4TB. Download 860 EVO firmware, driver, and more.

www.samsung.com

You are getting MORE than the specs say you should, ie, 2400MB/s vs spec of 550MB/s.
Turn OFF RAPID MODE as it is caching the test file then you will see more realistic number.

 

[USAFRet]

Hey all,

I just got a new SSD fairly recently and the results in Samsung magician seem "a bit" unrealistic (sarcasm). My read AND write speeds are in the range of 2,400-2,600 MB/S. That's near 20 GB/s. This is a SATA 6GB/S drive (my board doesn't even have any other internal storage interface). Why am I getting these results when they are clearly

You have RAPID mode turned on. It is mostly just reading the speed of your RAM.
Turn it OFF.

 

[inkydink815]

20GB/s? Don't you mean about 2.3GB/s?

 

[inkydink815]

a GB is aroudn 1000 MB.

so as above stated your only at 2.3GB/s(or 2.4 rounded)

 

[hnkenshiro]

20.8 gigabit/s = 2.6 gigabyte/s

SATA 6 is 6Gb/s.

byte = big B
bit = small b

Don't use them interchangeably.

and to be technical, the 2,600 mb/s you typed into google is like (2,600 millibit/s)

mega = big M
milli = small m

seconds = small s

 

[USAFRet]

Now that we've completely confused the OP with irrelevant numbers...

A stock Samsung 860 EVO should read around 550MB/s in the Samsung Magician performance test.
That it is reading 2,391 MB/s directly points to the RAPID mode being on.

It is using a chunk of your RAM as a cache for the SSD, and that is what causes the absurdly high Read/Write numbers.
In actual user performance, it does little or nothing.
Turn it OFF, and get use of that physical RAM back.

 

[computerjoe314]

The sata standard is the max through, not how much that drive will do.

 

[Solandri]

It is using a chunk of your RAM as a cache for the SSD, and that is what causes the absurdly high Read/Write numbers.
In actual user performance, it does little or nothing.
Turn it OFF, and get use of that physical RAM back.

This. Turn RAPID mode off.

The reason it makes little real performance difference is because every major OS already uses unused RAM as a disk cache. There's no point letting RAM sit unused, so the OS stuffs unused RAM full of data it read off the disk. If you need to use the RAM for something else, it's trivial to reallocate it to a program as if it were never used as a cache. If you do need that data again, hey! Lucky you! It's right here in RAM so you don't need to read the disk again. It's a no-lose situation.

The only thing RAPID mode does that the built-in OS disk cache does not is hide the fact that you're using a RAM cache from benchmarking programs (which specifically bypass the OS disk cache). So the benchmarks you run end up measuring RAM speed instead of disk speed. The only time it actually helps is if you specifically need to preserve disk speeds even though RAM utilization is approaching 100%. But in that case you're better off just buying more RAM.

In the opposite case, where you're approaching 100% RAM utilization but disk speed isn't important, it actually hurts performance by forcing the OS to swap programs out of RAM to the pagefile (because a chunk of the RAM is reserved for the RAPID disk cache).