On 14/03/2021 21.00, Tim via users wrote:
When I do something like:
dd if='fedora.iso' of=/dev/sdb status=progress
I only get around 6 megabytes per second on a USB 2 Sandisk Cruzer
Blade flashdrive (store bought, not fleabay) plugged directly into a
motherboard's USB 3 port - one that's not sharing its host with any
other ports in use.
Surely it should be going a lot faster?
Not in my experience, this is what one often gets with many USB2 disks. They go much
faster reading from USB.
When plugged in, dmesg shows this for the drive:
[337595.365826] usb 1-4: new high-speed USB device number 24 using xhci_hcd
[337595.489415] usb 1-4: New USB device found, idVendor=0781, idProduct=5567, bcdDevice=
1.00
[337595.489426] usb 1-4: New USB device strings: Mfr=1, Product=2, SerialNumber=3
[337595.489433] usb 1-4: Product: Cruzer Blade
[337595.489439] usb 1-4: Manufacturer: SanDisk
[337595.489445] usb 1-4: SerialNumber: 00007014102520061826
[337595.557718] usb-storage 1-4:1.0: USB Mass Storage device detected
[337595.557933] scsi host6: usb-storage 1-4:1.0
[337595.557995] usbcore: registered new interface driver usb-storage
[337595.560673] usbcore: registered new interface driver uas
[337596.561807] scsi 6:0:0:0: Direct-Access SanDisk Cruzer Blade 1.00 PQ: 0
ANSI: 6
[337596.562686] sd 6:0:0:0: Attached scsi generic sg2 type 0
[337596.563276] sd 6:0:0:0: [sdb] 60088320 512-byte logical blocks: (30.7 GB/28.6 GiB)
[337596.564047] sd 6:0:0:0: [sdb] Write Protect is off
[337596.564057] sd 6:0:0:0: [sdb] Mode Sense: 43 00 00 00
[337596.564305] sd 6:0:0:0: [sdb] Write cache: disabled, read cache: enabled, doesn't
support DPO or FUA
[337596.584964] sdb: sdb1
[337596.586991] sd 6:0:0:0: [sdb] Attached SCSI removable disk
[337609.674186] usb 1-11: USB disconnect, device number 19
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Eyal Lebedinsky (fedora(a)eyal.emu.id.au)