Debug-action-cache [ PREMIUM ]

The first and most critical step in your debugging journey is to enable the secret, detailed logging that GitHub Actions normally hides from you. There are two primary levels of debug logging you need to know about.

By mastering debug-action-cache , you’ll turn an opaque cache system into a transparent, tunable performance booster.

Source files that change on every build (e.g., a file containing a build timestamp). debug-action-cache

Always provide an ordered list of fallback prefixes in the restore-keys section. If an exact match fails, GitHub will pull the most recent cache matching the prefix, preventing a complete cold start.

The debug-action-cache operates on a simple yet effective principle: The first and most critical step in your

You haven’t changed any dependencies, yet the CI pipeline insists on downloading the entire internet on every single commit.

The exact version of the compiler or linter being executed. Source files that change on every build (e

If you want to force a clean slate via code, append a version number string to your cache key name (e.g., change v1 to v2 ).

If the hash changes between two runs where you made no dependency changes, an automated script (like an internal linter or formatter) is altering the file mid-run. 4. Leverage Cache Eviction Clearances

restore-keys: | $ runner.os -node-$ hashFiles('package-lock.json') # exact same hash $ runner.os -node- # any older node cache – use as last resort

At its heart, debug-action-cache refers to the process of enabling verbose logging, analyzing cache keys, inspecting saved artifacts, and understanding the inner workings of the actions/cache and actions/cache/save actions. While not an official command, the term has emerged in developer communities as a shorthand for “debugging GitHub Actions cache problems.” It encompasses: