Intel 750 : high read latency

[NMICH1]

Hello,

I am using a 400gb Intel 750 (pcie card) on a Z97 board.

Using AS SSD, I find that the read latency is about 4 times higher than what I see from reviews (0.08ms vs 0.02ms). The write latency is ok. The 0.02ms seems in line with the specs of the drive, so it appears that my system is slow.

I tried moving to the CPU lanes to see if that was a factor. As expected, I got a nice boost in seq read, but no change in latency :

Example from the web (Google image search for "intel 750 asssd") :

Any idea of what I should look for to obtain "normal" read latencies ? I tried disabling real-time protection in Windows Defender, but no change there.

Platform :

Windows 10 AU

NVME driver 1.7

Intel 4790k

16 Gb RAM

Maximus VII Hero (Z97)

Intel 750 400Gb

[idata]

Latenic,

We are going to check this for you and will advise very soon. In the mean time, if you have any further questions, please do not hesitate to contact us.Best regards,Aleki

[NMICH1]

Thanks !

I've tried disabling all the Windows file filters I could, but I couldn't get the latency to budge.

I ran a complete check using SSD Toolbox, the drive appears healthy.

[idata]

Latenic,

Thank you for your time. Taking advantage of the direct path from the storage to the CPU by means of NVMe, the Intel®SSD 750 Series exhibits low latency of less than 20 μs for sequential accesses. See the http://www.intel.com/content/dam/www/public/us/en/documents/product-specifications/ssd-750-spec.pdf Intel® Solid-State Drive 750 Series Product Specification on page # 9 for more information.For further information on this you can also check this documentation:http://www.intel.com/content/dam/support/us/en/documents/ssdc/hpssd/ssd-750/sb/intel_ssd_750_series_... Intel® Solid-State Drive 750 Series - Evaluation Guide from page # 13 on where it shows the method used by Intel for accurate results.Please, let us know if this helped you.Best regards,Aleki

[NMICH1]

Hello,

This did not help.

Unless I'm mistaken, the linked guide only shows how to measure throughput - not latency (in fact, in the screenshots in the guide, average latency is above 3ms).

Is there a guide on how to measure the 20 μs latency ?

(I ran the iometer setup in the guide, the result is below)