SAN19-114 To control or not to control I/O? скачать в хорошем качестве

SAN19-114 To control or not to control I/O?

Important stakeholders in the personal-OS arena have switched to the BFQ I/O scheduler, to endow their systems with a very low I/O latency. The story differs with enterprise systems tough. By controlling I/O with BFQ, these systems would reach a 5X-10X throughput boost. Nevertheless, almost all stakeholders still stick to uncontrolled I/O. For various reasons they fail to see the economic benefits that may follow from the above boost. At the other end of the spectrum, Facebook seems to see these benefits so clearly that they have invested in the design and implementation of two brand new I/O controllers for Linux. The latter control, respectively, latency and bandwidth. And these are the two main goals of BFQ. In this presentation we try to shed a light on this sort of controversial situation, by showing some performance figures. In particular we show again (the poor) performance without I/O control, after which we compare the performance of these new controllers with that of BFQ.