simultaneous copy to multiple media

[Jacek Trzmiel]

Claudio Grondi wrote:
> I am on a Widows 2000 box using the NTFS file system.
> Both up to now suggested approaches as
> - tee.exe (where I used the http://david.tribble.com/dos/tee.exe
> DOS-port with redirecting stdout to NULL) and
> - parallel copy (hoping caching does the job) are by far
> slower than the consecutive copy:
>   single copy speed 12-15 MByte/s
>     which gives effectively
>       6-7 MByte/s,
>   tee.exe or twice copy in parallel
>       1-3 MByte/s.
> 
> Any other suggestions except writing an own
> optimised version of tee.exe

Try this:
  http://mastermind.com.pl/multicopy/

This is small tool I've wrote, that does use large memory buffers with
asynchronous I/O to copy file.  

Following command:
  multicopy c:\testfile d:\testfile e:\testfile f:\testfile
will copy c:\testfile to d, e and f disks.

With four separate IDE disks I can copy file at about 30MB/s, which
means 120MB/s total I/O.  You can give it a try, but I don't know if it
will work fast with USB drives.

HTH,
sc0rp.