adding boot time options to the sg driver does not work

[Lancashire, Pete]

I'm trying to change def_reserved_size from the default of 32768 to what I belive is the maximum
of 1048576 bytes ( 1 Megabyte ) upon boot

In /etc/modprobe.d I createf the file sg.conf with the line

options sg def_reserved_size=1048579

did modprobe -c, it reconized the new file and did not throw an error.

I then rebooted

cat /proc/scsi/sg/def_reserved_size returns 32768

What am I doing wrong ?