USB3 Write Speeds very slow on External SSD

[setq]

@Eric_Tan Try add an oflag=direct

rock@rockpie:~$ sudo dd if=/dev/zero of=/mnt/ntfs bs=4M count=100 status=progress
406847488 bytes (407 MB, 388 MiB) copied, 23 s, 17.7 MB/s
100+0 records in
100+0 records out
419430400 bytes (419 MB, 400 MiB) copied, 23.7275 s, 17.7 MB/s

rock@rockpie:~$ sudo dd if=/dev/zero of=/mnt/ntfs bs=4M count=100 status=progress oflag=direct
394264576 bytes (394 MB, 376 MiB) copied, 4 s, 97.6 MB/s
100+0 records in
100+0 records out
419430400 bytes (419 MB, 400 MiB) copied, 4.30003 s, 97.5 MB/s

[Eric_Tan]

The following are my read/write speeds (on NTFS external USB mounted SSD) - All using the same SSD and external case.

Rock64 (USB3) = 260/25.2 (running Armbian OS)

Rock64 (USB3) = 100/16 (running RockPi E OS)
Rock E (USB3) = 96/16.4mb (running RockPi E OS)

Rock S (USB2) = 29/6mb (running RockPi S OS)

sudo dd if=/dev/zero of=/mnt/ntfs/test2 bs=8k count=50k oflag=direct; sudo rm -f /mnt/ntfs/test2

51200+0 records in
51200+0 records out
419430400 bytes (419 MB, 400 MiB) copied, 15.1767 s, 27.6 MB/s

sudo hdparm -t /dev/sda

/dev/sda:
Timing buffered disk reads: 294 MB in 3.01 seconds = 97.69 MB/sec

Write speeds seems to be higher, based on the “oflag=direct” options… but not sure why my read speeds are not as high as 200mb+ as per the armbian image

PS: I re-imaged the Debian Rock Pi E image from Rock Pi site, before starting tonights test

[Eric_Tan]

rock@rockpie:/mnt/ntfs$ sudo hdparm -Tt /dev/sda1

/dev/sda1:
 Timing cached reads:   928 MB in  2.00 seconds = 463.79 MB/sec
 Timing buffered disk reads: 330 MB in  3.00 seconds = 109.98 MB/sec

rock@rockpie:/mnt/ntfs$ sudo hdparm -Tt /dev/sda1

/dev/sda1:
 Timing cached reads:   916 MB in  2.00 seconds = 458.05 MB/sec
 Timing buffered disk reads: 336 MB in  3.02 seconds = 111.43 MB/sec

My tests running your settings

rock@rockpie:/mnt$ sudo hdparm -Tt /dev/sda

/dev/sda:
Timing cached reads: 954 MB in 2.00 seconds = 476.28 MB/sec
Timing buffered disk reads: 262 MB in 3.01 seconds = 87.13 MB/sec

rock@rockpie:/mnt$ sudo dd if=/dev/zero of=/mnt/ntfs/test.txt bs=512k count=2048 oflag=direct2048+0 records in
2048+0 records out
1073741824 bytes (1.1 GB, 1.0 GiB) copied, 10.8704 s, 98.8 MB/s

OK, tested based on your settings, and I am getting very similar numbers as you… the only problem is… mine is SSD… hahah… and its the same speed as your HDD…

I tested with an USB3 external HDD, and am getting 80mb reads and 80mb writes, based on your setting…

Tested the SSD in my Windows Machine and gets 350+ read/write speeds… so the SSD is fine…