BUG/MINOR: pool/cli: use ullong to report total pool usage in bytes

As noticed by Gabriel Tzagkarakis in issue #1903, the total pool size
in bytes is historically still in 32 bits, but at least we should report
the product of the number of objects and their size in 64 bits so that
the value doesn't wrap around 4G.

This may be backported to all versions.
1 file changed