Arnold can generate a log reporting all the steps needed to render an image, as well as any warnings and errors encountered by the renderer. This log also provides detailed statistics that are useful for debugging, optimizing and benchmarking renders. Note that an individual log file will be saved for each frame of animation that has been rendered.
Log to File
If enabled a log is written to the specified file.
Log Verbosity
Specifies the amount of information in the log messages, with Warnings being least and Debug most:
Max. Warnings
Limits the number of warning messages (of a similar type) that are sent to the log.
Log To Console
Enables logging to the console.