slob

SLOB, short for Silly Little Oracle Benchmark, is an open-source benchmarking tool used to evaluate the input/output I/O subsystem performance of Oracle databases. It focuses on disk I/O rather than CPU or memory performance and is designed to be simple to configure and repeat.

The tool simulates Oracle workload by launching multiple worker processes that perform read and write operations against database storage, with configurable parameters such as the number of workers, block size, read/write ratio, and the locality of I/O. It supports different I/O patterns, including random and sequential access, and can model various durations and concurrency levels.

SLOB generates benchmark results that typically include metrics such as IOPS (input/output operations per second), throughput (MB/s), and latency, often accompanied by a compact report and optional CSV data for external analysis. It is frequently used for evaluating storage subsystems, tuning Oracle I/O performance, and comparing storage configurations during capacity planning.

The tool is community-supported and widely used on Linux and UNIX systems with Oracle databases or clients. As a lightweight, repeatable benchmark, SLOB is commonly cited in Oracle performance discussions and in storage vendor demonstrations as a means to assess I/O performance under realistic workloads.

See also: related database benchmarking tools and approaches to I/O testing.