Samsung 950 Pro - AS SSD write speeds

[Timmah!]

So, i tried to bench my new M2 SSD with AS SSD, just to see if it runs in line with what i should expect, and uh - its not? Especially write speeds in AS SSD are totally terrible. Any idea if there is something wrong with the drive, my system or its some AS SSD related issue?

i tried CrystalDisk Mark as well and while i dont know if the numbers are right, they certainly look more acceptable.

 

[UsandThem]

The Crystal Disk results look in line with what others have posted. Have you tried benching it in Samsung Magician?

If it looks good in there, I wouldn't be very concerned with the AS SSD results. It could be a bug depending on the version.

 

[Hail The Brain Slug]

I've regularly had odd results from as-ssd on any drives I've tested. I stopped using it because the results are obviously incorrect.

 

[Billy Tallis]

Either install Samsung's NVMe driver, or disable write cache buffer flushing on the 950 Pro. The Windows NVMe driver has some unusual behaviors when it comes to write caching and ensuring that the application's wishes regarding data safety are respected. In a way, it is actually a good sign when your benchmarking tool runs afoul of this quirk, because it means that the tool has definitely ensured that it is testing the performance of the drive itself and not merely the filesystem's cache. The downside is that Microsoft's NVMe driver has different behavior from their AHCI/SATA driver, and those differences are not adequately documented. I'll have an article up soon showing how different SSDs are affected by this differently.