Hello,
I am using a Laptop 16 with the Dual M.2 extension card Under Ubuntu Desktop 22.04.1
So I have 3 nVME SSDs in the system, the 2 WD on the motherboard and 1 Lexar NM790 2TB on the extension card.
I am using my laptop as a desktop, meaning the cover is closed, AC is always on, using external screen (HDMI via laptop port).
Other devices connected are keyboard, mouse, webcam, bar code scanner and infra-red sound remote control; all via a USB (via USB-A laptop port) Dell docking station.
Last is an external 2.5Gb/s RJ45 network interface via laptop USB-C port.
WIFI and Bluetooth are off.
When I benchmark each SSD individually, results comply with SSD specs (between 5000 and 7000 MB/s for sequential load).
The problem is that transferring big ISO files (close to sequential load) from any SSD to any other one (so being on motherboard or on extension card) is limited to a deceptive 1.3GB/s !
Copying my big “Document” tree (close to random small files load), the speed is around 650MB/s (half the speed for random small files looking normal to me).
For copying big ISO files, I was expecting to see something between 4 and 5GB/s as transfer speed.
Is that normal or is there something wrong somewhere ?
Thanks for your help
Eric Collart