Re: df incorrectly handles volumes > 4TB

[Paul Eggert]

address@hidden writes:

> This is how a 4.5TB filesystem with ~400GB of data on it is displayed with df
> from coreutils-5.2.1.
>
> nkfb0 root # df -H
> Filesystem             Size   Used  Avail Use% Mounted on
> ...
> /dev/archive/scr0      601G   412G   183G  70% /scr0
> ...
> strace -v df -k /dev/archive/scr0
> ...
> statfs("/scr0", {f_type="EXT2_SUPER_MAGIC", f_bsize=4096, f_blocks=146499832, 
> f_bfree=80165081, f_bavail=78697075, f_files=9318400, f_ffree=9282355, 
> f_fsid={0, 0}, f_namelen=255, f_frsize=4096}) = 0

statfs is claiming that there are 146,499,832 blocks, each of size
4096 bytes, which works out to 600,063,311,872 bytes total, so df's
"601G" faithfully reflects what the system call is telling "df".

Most likely, then, the bug is not in "df" itself.  I'd look for bugs
in the underlying C library, or operating system, or file system, etc.
4.5 TB is just over 2**30 * 4096 bytes, so perhaps your file system
can't handle more than 2**30 blocks for some reason.