NanoLog: A Nanosecond Scale Logging System

NanoLog is a nanosecond scale logging system that is 1-2 orders of magnitude faster than existing logging systems such as Log4j2, spdlog, Boost log or Event Tracing for Windows. The system achieves a throughput up to 80 million log messages per second for simple messages and has a typical log invocation overhead of 8 nanoseconds in microbenchmarks and 18 nanoseconds in applications, despite exposing a traditional printf-like API. NanoLog achieves this low latency and high throughput by shifting work out of the runtime hot path and into the compilation and post-execution phases of the application. More specifically, it slims down user log messages at compile-time by extracting static log components, outputs the log in a compacted, binary format at runtime, and utilizes an offline process to re-inflate the compacted logs. Additionally, log analytic applications can directly consume the compacted log and see a performance improvement of over 8x due to I/O savings. Overall, the lower cost of NanoLog allows developers to log more often, log in more detail, and use logging in low-latency production settings where traditional logging mechanisms are too expensive.