Logging

Logging

UCS has logging infrastructure. logging is controlled by a single level.

NOTE
By default, a release build limits the log level to 'debug' for better performance.
In order to enable all log levels, use ./contrib/configure-devel (instead of ./contrib/configure-release) to build UCX.

• fatal - stops the program
• error - an error which does not stop the program and can be reported back to user.
• warn - a warning which does not return error to the user.
• info
• debug - debugging messages, low volume, about initialization/cleanup.
• trace - debugging messages, high volume, during runtime, for “special” events.
• req - details of every send/receive request and tag matching.
• data - headers of every packet being sent/received.
• async - async notifications and progress thread.
• func - function calls and arguments.
• poll - same as func, but also for functions which do busy-polling.

Rules:

• UCX_LOG_LEVEL controls the logging level.
• When log level is selected, it enables all messages with this level or higher.
• Logging messages can be sent to stdout (default) or to a file by setting UCX_LOG_FILE

Features:

• It's possible to define maximal log level during compile time, to avoid checks in release mode.
• It's possible to install custom log message handler.