Parallel I/O Aware Query Optimization

17 Jun 2015

Parallel I/O Aware Query Optimization on Sigmod 2014.

This paper improves the parallelism in SSDs by allowing deeper I/O query depth. The motivation is based on a simple observation: the SSDs’s random I/O performance improves when increasing the queue depth.

parallel_reads

This is because increasing the queue depth can improve the parallelism utilization in SSDs.

A modern SSD is capable of utilizing multiple levels of parallelism; namely, plane level, channel-level, package level, and die level parallelism.

Almost all modern SSDs support command queuing mechanism, such as Native Command Queuing (NCQ) and Tagged Command Queuing (TCQ).

This paper improves the database I/O parallelism by introducing multiple concurrent workers:

database_scan