Hi:

 

Just curious if anyone knows if this limit has changed or will change in
the future?

We have some users asking about it.

 

Thanks,

 

Tim Rushforth

City of Winnipeg

 

 

Forum:   ADSM.ORG - ADSM / TSM Mailing List Archive 
 Date:      2003, Jan 06 
 From:      Jim Smith <nobody at nowhere.com
<mailto:nobody%20at%20nowhere.com> > 

Tim,
 
Actually, two different behaviors based on two-different problems.
Files
that start less then 2 GB but grow > 2 GB will continue to use subfile
backup as long as the other requirements for the base file (i.e., the
file
on the client cache) is still valid.  The limiting factor here is that
there is only 32-bit support in the differencing subsystem that we are
using.  We chose 2 GB on the onset (instead of 4 GB) as the limit to
avoid
any possible boundary problems near the 32-bit addressing limit and also
because this technology was aimed at the mobile market (read: who is
going
to have files on their laptops > 2 GB).  I understand that there are
several shops that use this technology beyond the laptop environment.
Ultimately, the solution is to have a 64-bit subsystem in place so that
we
can go beyond 4 GB.  I suggest a requirement to Tivoli if this is
important to your shop.
 
The low-end limit (1024 bytes) was due to some strange behavior with
really small files, e.g., if a file started out at 5 k and then was
truncated to 8 bytes.  The solution was to just send the entire file if
the file fell below the 1k threshold.  We can get away with resending
these small files because ... they are small files!  It is probably a
wash
to resend or to try to correctly send a delta file in this case.
 
Hope this helps.
 
- Jim
 
J.P. (Jim) Smith
TSM Client Development
smithjp AT us.ibm DOT com <mailto:smithjp%20AT%20us.ibm%20DOT%20com>