Samsung SM951 AHCI SSD Performing Poorly At Sub-4k File Sizes

[Mako360]

Hmmm, comparing my newly installed SM951 to scores that are posted on various review sites, and it's performing extremely well in the larger file read/writes, nearly identical to others results, but is getting killed in 4k tests...particularly high que depth 4k tests.

It's about -45% lower than the marks should be in the following specific test spots:

Anvil 4K QD16 : Scores 98,473 IOPS, should be around 150,000 IOPS

ATTO - Everything Below 64.0 K: Scores are off on 0.5 through 64.0 by -30 to -50%, then magically catch back up to 100% where they should be by 256.0...odd)

CrystalDiskMark 4K Q32T1: Scores 337.2/308.8 while it should be around 512/450

AS SSD 4K-64Thrd: Scores 400/361 while it should be around 680/360

ASS SSD Copy-Benchmark, "Program": Scores 417 MB/s with a 3.37 s duration, should be around 780 MB/s with a 1.80 second duration

HD Tune Pro 5.50 4K random multi (32): 47202 IOPS, should be around 100000 IOPS

I'm running Windows 7 on an MSI X99S Gaming 7 (4x lanes)...any particular OS setting or something that should be checked that would affect the smaller file transfers?

It's strange because what I've listed above are the only areas within each benchmark that were off, the other 20+ measurements within those tests were spot on. Wonder what I'm missing.

My full benchmark results: http://i.imgur.com/iKny0sj.jpg

 

[Butcher9_9]

Is it you OS drive?

If so that's most likely the cause. Most sites will benchmark with a separate OS drive.

 

[Mako360]

Is it you OS drive?

If so that's most likely the cause. Most sites will benchmark with a separate OS drive.

No, secondary drive with just a few game installs on it. Good thought though.

I'm thinking it's something within Windows 7, a setting, registry entry, etc.

 

[Not a John]

Looks like you didn't install Intel RST drivers. They will increase 4k-64 thrd score considerably and 4k read and write scores slightly. Real world gains will be close to nothing though.

 

[Mako360]

Looks like you didn't install Intel RST drivers. They will increase 4k-64 thrd score considerably and 4k read and write scores slightly. Real world gains will be close to nothing though.

Thanks John, was wondering about that. Will try it.

 

[Mako360]

No dice on IRST, they don't currently support PCI-E drives (including M.2) so I drew a dead end there unfortunately.

I disabled C-States thinking maybe it was a power issue, but that didn't make a difference. For whatever reason as the days pass the drive is getting worse and worse on small file sizes, currently it's logging benchmark results that are 3-4x slower than where it should be if the file size is 32KB or smaller...

It's wild because on larger files it performs where it should, around 2000+MB/sec, but on the smaller ones, look out below, it's as slow now as a traditional platter HD.

Test run just now, all numbers for 32.0KB and smaller should be 300-400% higher:

Here's how the drive should perform, nearly identical rig as mine:

 

[sk3tch]

Any resolution here? Now that NewEgg carries this - contemplating picking one up. But this issue, coupled with lack of manufacturer warranty - has me turned off.