I am using an enclosure that has the JMicron JMS567 SATA 6Gb/s bridge as a controller.
I am also using the My Book Duo which has a WD controller.
Both report same speeds.
File systems are
Both have write speed about 250 MB/s on my Mac Air.
On the Raspberry Pi I can reach maximum of 60 MB/s.
I spent day and night to figure out how to improve because I thought that I could have faster speeds.
I went through whole process of searching the internet for whatever hint I can find. To no avail. The Raspberry Pi always applies a quirk for usb-storage for the JMicron controller and refuses to use uas for example. I tried plenty, too long to list and too tired of it.
Anyway, I came to the conclusion that that is the best best the Pi can offer. But I want to be sure and would like to ask.
What is the expected speed one can expect from the Pi if I transfer data from one external HDD connected to the Pi to another external HDD connected to the PI. Both connected to the USB 3 plugs. Both report 250 MB/s speeds on Mac.
Or in other words is 60 MB/s normal for USB 3 on a Pi ?