> What is MG04ACA400N? It is a Toshiba 7200 RPM hard drive. > The above results are low enough such that these could come from a hard > disk. However, the test results are hard to interpret since the I/O > pattern is neither perfectly sequential nor perfectly random (32 > sequential jobs). Please provide separate measurements for sequential > and random I/O. > The above results show that this patch makes reading from a hard disk > slower. Isn't the primary use case of mq-deadline to make reading from > hard disks faster? So why should these two patches be applied if these > slow down reading from a hard disk? The data of MG04ACA400N on the raid controller is obviously different from the single disk, especially the reading data, I did not expect this situation, the data on the raid controller made me mistakenly think that the same applies to HDD. I will re-analyze the impact of this patch on the HDD later, please ignore it for now. Also, can I ask? If using fio or other tools, how should testing be done to get more accurate and convincing data? Such as the perfectly sequential and random I/O performance you mentioned above (fio's multi-threaded test does result in neither perfectly sequential nor perfectly random, but single thread dispatch is too slow, and cannot play the merge and sorting ability of elv). Thanks, Wang.
