+iodepth_batch_complete=int This defines how many pieces of IO to retrieve
+ at once. It defaults to 1 which means that we'll ask
+ for a minimum of 1 IO in the retrieval process from
+ the kernel. The IO retrieval will go on until we
+ hit the limit set by iodepth_low. If this variable is
+ set to 0, then fio will always check for completed
+ events before queuing more IO. This helps reduce
+ IO latency, at the cost of more retrieval system calls.
+