fio: how to write 2X user capacity?

My system has SSDs and I wanted to run some benchmark tests on it based on SSS PTS (SNIA). For example, for IOPS test, the spec suggested to use QD=32, TC=4 and for doing IO, the spec says following. Run SEQ Workload Independent Pre-conditioning - Write 2X User Capacity with 128KiB SEQ writes, writing the entire ActiveRange without LBA restrictions. My system has an SSD of size 12 TB, so I planned to invoke fio two times in sequence as below. fio --iodepth=32 --bs=128 --numjobs=4 --rw=write --size=3T ... # write 4*3T=12T fio --iodepth=32 --bs=128 --numjobs=4 --rw=write --size=3T ... # write 4*3T=12T But, from the first command only, I got fio: native_fallocate call failed: No space left on device. I think this is expected since, there are some other small files/dirs such as "lost+found". I think, I am doing something wrong here and there must be a better right way of doing this. Can somebody suggest me how should I parameterized my fio command so that it writes 2X user capacity as suggested in PTS spec? Thanks in advance.