bs=8k,32k means 8k for reads, 32k for writes and trims
bs=8k,32k, means 8k for reads, 32k for writes, and default for trims
bs=,8k means default for reads, 8k for writes and trims
bs=8k,32k means 8k for reads, 32k for writes and trims
bs=8k,32k, means 8k for reads, 32k for writes, and default for trims
bs=,8k means default for reads, 8k for writes and trims