[rdiff-backup-users] more info on 25gig files

[Clint Silvester]

I tried rdiff last night instead of rdiff-backup on the same 25 gig
files that rdiff-backup gave me an error 107 and rdiff worked fine on
the files.  I got a full copy of the newer file (what I was trying to do
with rdiff-backup).  This was just with standard options, no block size
changes or anything.  Here are the timings I got:

for the signature:

real    8m27.412s
user    3m36.976s
sys     1m21.662s

for the delta:

real    238m28.366s
user    227m32.673s
sys     1m40.479s

for the patch:

real    19m20.980s
user    0m23.942s
sys     3m20.326s

So that's over 4 and a half hours.  I'm thinking maybe I'll need to play
with block sizes but that only mentions changing the block sizes for the
signature file, so I don't know if it will make any difference for
creating the delta.  Anyway, I'll try some more things, but it looks
like rdiff doesn't suffer from the same problem rdiff-backup does.  I'm
still testing and it takes a while to run these.  I'll report back again.

Clint Silvester