Why SMB_ROUNDUP_ALLOCATION_SIZE so large

[Steve French]

It confuses those reading output from some of the common commands like
du that the SMB_ROUNDUP_ALLOCATION_SIZE is set so large (1MB) in local.h
(which is used by get_allocation_size) since it causes even 1 byte files
to apparently take 1MB of disk space - confusing as you read some Unix
commands on the client and see them differ so much from the same on ext3
on the server.   In addition this means samba differs significantly from
Windows  which has a much smaller minimum allocation size for files
(when you simply create a file and do "du -sk" on the new file to Samba
server)

Anyone know why this was set so high in Samba?

I would prefer a roundup value (if any) of 4K.