Bazel Remote Cache Debugger

This is a simple tool to compare 2 execution logs and scrape some cache hit metrics.

Features

• Compare two execution logs and collect the list of environment variables and inputs that are different across executions. Right now the tool doesn't compare command_args and other attributes of SpawnExec
• Consumes execution logs in binary format that have been produced directly by bazel. So no need to use any other tools to transform them beforehand.
• Produces output logs in both text and binary format so that the result can be consumed by other applications/tools based on output.proto

How to use

To see all supported commands just use --help/-h flag:
java -jar remote-cache-debugger.jar -h

To compare 2 execution logs:
java -jar remote-cache-debugger.jar -first <path_to_exec1.log> -second <path_to_exec2.log>

To compare execution logs and generate a text report:
java -jar remote-cache-debugger.jar -first <path_to_exec1.log> -second <path_to_exec2.log> -o <path_to_text_output>

To compare execution logs and generate a binary report:
java -jar remote-cache-debugger.jar -first <path_to_exec1.log> -second <path_to_exec2.log> -ob <path_to_binary_output>

Limitations

Hopefully, these limitations will be solved soon enough

• The tool doesn't compare all attributes of SpawnExec as mentioned above
• If you built another target or changed the flags/options/features of the build most probably results will be opaque
• If sequential execution log contains more inputs/environment variables the tool won't track it