Version 3 is outdated. Latest version today is 6.0.2.
Q is for queue depth, T is for threads, and not how it written in the article. 4k is block size, and not file size.
Results for all random 4k test are pretty the same for SATA interface. Q1T1 is the smallest, because there are no queue used, and SSD needs to wait for next command. On NVMe(PCIe) disk can benefit from unlimited queue depth and number(threads).