Select the appropriate log level based on operational significance and ensure messages are clear, accurate, and formatted for human readability: 1. **ERROR**: Use for failures requiring immediate attention 2. **WARN**: Use for unusual but non-critical situations 3. **INFO**: Use for significant but normal operations 4. **DEBUG**: Use for detailed diagnostic information that won't impact performance Consider the frequency and volume of log entries when selecting levels. High-frequency operations should use lower log levels (DEBUG) to avoid log pollution and performance degradation. Format log messages for runtime readability with variables logically positioned: ```rust // Bad - Poor readability in runtime logs warn!( "could not create image layers due to {}; this is not critical because the requested image LSN is below the GC curoff", err ); // Good - Clear and readable at runtime warn!( "failed to create image layers but lsn is <= gc_cutoff, therefore this can happen: lsn={lsn} gc_cutoff={gc_cutoff}: {err}", ); ``` Ensure log messages accurately describe the operation being performed and provide meaningful context. Avoid logging routine operations in tight loops, especially at higher log levels.