USB 2.0 External Drive - What Is A Reasonable Transfer Rate?

[Drew Tomlinson]

Hans Petter Selasky wrote:
> On Thursday 23 July 2009 04:38:35 Drew Tomlinson wrote:
>   
>> I have a USB 2.0 external drive that's formatted as NTFS under Windows
>> XP.  I've plugged it into my 8.0 BETA2 install and am copying files to a
>> local raid1z zpool with one vdev consisting of 4 drives.  I'm trying to
>> move about 100 GB of assorted files and have been at it all day.  The
>> USB drive contains assorted files such as mp3, CD/DVD images, zip,
>> documents, etc.  I'm guessing most files range between 1 - 4 MB with
>> some as large as 4 GB.
>>
>> Anyway, iostat shows the transfer rate  at around 2 - 3 MB per second.
>> Is this all I should expect from a USB 2.0 drive?  Is there anything I
>> can do to speed this up?
>>     
>
> Hi,
>
> Benchmark your device like this:
>
> dd if=/dev/daX of=/dev/null bs=65536
>
> It will give you the correct transferrate number.
>   

Thanks.  When using your suggestion, iostat shows rate at almost 34 MB 
per second which seems reasonable.

When copying a large file to /dev/null as suggested by Erich Dollansky, 
I get right around 10 MB per second.

So does that mean that it's the NTFS driver that's causing the slowing?

> Maybe there are some utilities in /usr/ports that can read NTFS faster than 
> the kernel NTFS driver.
>   

Maybe I'll have a look at /usr/ports/sysutils/fusefs-ntfs as suggested 
by Gary Jennejohn.

Thanks,

Drew

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