"need a quick hashing method"

[Loïc Grenié]

2010/11/22 Arthur Bela <jozsi.avadkan at gmail.com>:
> HDD#1
> HDD#2
>
> I copy files between HDD#1 and HDD#2.
>
> When i finish, i need a quick "hasing method" - i just want to check,
> that the copy was 100% ok.
>
> md5sum, sha256sum is slow -> are there any "very fast" hash algoritms?
> - just for checking if the copied file is corrupt or not [i just need
> to know, if there were even 1 Byte error when copying]
>
> i can write the script, that checks the files, i just need a hash
> algoritm [""software/command""], that is fast enough.

    Since you want to verify everything, the best you can do is just
  to use diff. No hashing, just reading the data and comparing
  (which is more than 10000 times faster than the reading on the
  disks, thus negligible).

       Hope this helps,

              Loïc