Slow External HDD File Transfer

[Robin]

I have an older USB 2.0 HDD caddy that I'm transferring large files to (10-15GB) and it's taking around 30 minutes for each one with a max speed
of around 7 MB/s. USB 2.0 should have a speed of around 35 MB/s which would be tolerable.

I don't know why it's going so slow, from a USB 2.0 or 3.0 laptop gives the same speed. Anyone know if there is any setting in Windows I need to adjust? Is it just that the single large file rather than lots of little ones is causing this? The drive is 3.5" 7200 RPM.

 

[TB]

I think it comes down to real world transfer speed being significantly less than the stated max speed.

 

[Robin]

I think it comes down to real world transfer speed being significantly less than the stated max speed.

USB 2.0's theoretical max speed is 60 MB/s, of course nothing ever reaches that and checking around 35 MB/s should be the realistic transfer speed. I don't mind waiting but half an hour a file is a bit ridiculous, 7 MB/s just seems a bit too slow like something is wrong.

 

[Grayfox]

The speed is dependent on the type of files as well as devices plugged in.
Lots of little files will slow down the transfer.
As the drive has to move the head to the next free space to write the file, then move the head to sector where the file table its to write the files location, then move the head to the next free space and so forth.
If the drive is fragmented this can make it even slower.

Also.
Try un-mounting the drive and remount it in another port.
Had an issue the other day where the file transfer was at 1MiB/s so I removed the drive and reinserted it, bam went to 16MiB/s
Can only assume the drivers went into USB 1 mode for some reason.

I think it comes down to real world transfer speed being significantly less than the stated max speed.

USB 2.0's theoretical max speed is 60 MB/s, of course nothing ever reaches that and checking around 35 MB/s should be the realistic transfer speed. I don't mind waiting but half an hour a file is a bit ridiculous, 7 MB/s just seems a bit too slow like something is wrong.

This is my biggest gripe with the USBs forums advertising of the USB Speed.
They do it to make it sound faster than it really is.
Yes I know about the overhead and other crap, but still.
Dont factor that in.

Even today going from NVMe SSD on the PC to an NVMe external drive the maximum you will get on USB 2 is ~40MB/s.
But advertising 350Mbps speed does not sound as good as 480Mbps.

But then again the USB forum have shown they're a bunch of idiots.
USB 3 will become USB 3.1 gen 1 which then will become USB 3.1 gen 2.

 

[Robin]

The speed is dependent on the type of files as well as devices plugged in.
Lots of little files will slow down the transfer.
As the drive has to move the head to the next free space to write the file, then move the head to sector where the file table its to write the files location, then move the head to the next free space and so forth.
If the drive is fragmented this can make it even slower.

The single large file then should in theory go faster, I dread to think the speed I would get with 15GB of tiny files! The drive was freshly wiped and formatted and it was going at 7 MB/s from even the first file.

Also.
Try un-mounting the drive and remount it in another port.
Had an issue the other day where the file transfer was at 1MiB/s so I removed the drive and reinserted it, bam went to 16MiB/s
Can only assume the drivers went into USB 1 mode for some reason.

I will give other ports a go, also thinking of trying some other USB cables as well. I have also heard Windows can have driver issues with things like this. There were some recommendations about altering the Write-Caching Policy to make it go faster but I'm not sure it's a good idea.

This is my biggest gripe with the USBs forums advertising of the USB Speed.
They do it to make it sound faster than it really is.
Yes I know about the overhead and other crap, but still.
Dont factor that in.

Even today going from NVMe SSD on the PC to an NVMe external drive the maximum you will get on USB 2 is ~40MB/s.
But advertising 350Mbps speed does not sound as good as 480Mbps.

But then again the USB forum have shown they're a bunch of idiots.
USB 3 will become USB 3.1 gen 1 which then will become USB 3.1 gen 2.

The USB standard really is a complete mess, especially USB-C which is anyone guess as to what you get with the various cables and devices using it.

Hopefully USB 4.0 which seeks to finally unify everything under one standard (Thunderbolt 3) will sort all this out, but I'm sure they will still use inflated performance figures!

 

[Grayfox]

There were some recommendations about altering the Write-Caching Policy to make it go faster but I'm not sure it's a good idea.

You can get better performance if you enable Write Caching in windows.
This will make the flash drive controller use the built in DRAM.