  I/O latency and throughput is one of the major performance bottlenecks for
disk-based database systems. Upcoming persistent memory (PMem) technologies,
like Intel's Optane DC Persistent Memory Modules, promise to bridge the gap
between NAND-based flash (SSD) and DRAM, and thus eliminate the I/O bottleneck.
In this paper, we provide one of the first performance evaluations of PMem in
terms of bandwidth and latency. Based on the results, we develop guidelines for
efficient PMem usage and two essential I/O primitives tuned for PMem: log
writing and block flushing.
