SSD Speed on Dell XPS 13 9350 with Samsung EVO 970 Plus

In continuation of blog-post SSD Speed on Dell XPS 13 9350, here are performance measurements for a Samsung EVO 970 Plus in Dell XPS 13.

Caveat from Dell xps 13 9350 and Samsung 970 evo M.2 nvme Compatability?:

However, be aware that although the XPS 13 9350 uses a PCIe x4 configuration for its NVMe interface, the lanes are run in power saving mode, not max performance mode, and this cannot be changed by the user. 4 lanes in power saving mode is roughly equivalent to 2 lanes in max performance mode, so the result is that your sequential read and write speeds will max out at 1.8 GB/s, even though the 970 Evo can do much more than that.

Installing the new Samsung EVO 970 Plus.

Mounted in laptop:

Read speed of unencrypted disk:

Once again read speed, this with a LUKS encrypted disk:

SSD Speed on Dell XPS 13 9350

In Hard-Disk and SSD Speed Comparisons I compared a Mushkin SSD with 60 GB against a ADATA with 128 GB against a Seagate 1 TB hard disk drive. The SSD’s had roughly three times the speed of the hard disk drive. I.e., 380 MB/s vs. 134 MB/s for reading Mushkin vs. Seagate, and 297 MB/s vs. 131 MB/s for writing ADATA vs. Seagate.

I also compared USB-thumb-drives against above Seagate 1 TB hard drive in Hard-Disk and USB Drive Speed Comparisons. Read times were comparable (100-200 MB/s), while for writing the Seagate drive was roughly 4 to 5-times faster (100 MB/s vs 20 MB/s).

Hard drives speeds and prices in 2013 are given in Harddisk Drive Speed in MB/s. Read speeds are roughly 200 MB/s for enterprise drives.

Now the read- and write-speeds of the SSD in the Dell XPS 13 9350 are quite astonishing: up to 1.5 GB/s for reading, 532 MB/s for writing. Even if you use LUKS/dm-crypt the values are 840 MB/s for reading, and 428 MB/s for writing. Below are the measurements using gnome-disk-utility.

Without encryption:
Screenshot from 2016-07-17 14-47-25

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ext3 vs. ext4

Recently I installed an additional SATA drive on my Lenovo laptop. Without much ado I formatted the drive to ext4. Unfortunately, I quickly realized that the hard drive is spinning almost twice a second. My first drive on the laptop is also formatted with ext4, so using ext4 was a natural choice. A Google search revealed that I am not alone with this problem (USB Drive Blinks Constantly on EXT4 Format), and pointed out that formatting with ext3 can cure the problem. Which it indeed did.

The morale is: Newer is not always better.