In a distributed environment unified error logging and reporting is a crucial capability for debugging and monitoring. BigJob has a configurable logging system that captures debug, info, warning and error messages across its runtime and SAGA’s middleware adaptors. The logging system can be controlled in two different ways: via env_vars variables, which should be sufficient in most scenarios, and via the bigjob.conf file.
Several environment variables can be used to control SAGA and BigJob’s logging behavior from the command line. Obviously, this can come in handy when debugging a problem with an existing SAGA/BigJob application. Environment variables are set in the executing shell and evaluated by BigJob at program startup.
Controls the log level. This controls the amount of output generated by the logging system. BIGJOB_VERBOSE expects either a numeric (0-4) value or a string (case insensitive) representing the log level:
| Numeric Value | Log Level | Type of Messages Displayed |
|---|---|---|
| 0 (default) | CRITICAL | Only fatal events that will cause BigJob to abort. |
| 1 | ERROR | Errors that will not necessarily cause BigJob to abort. |
| 2 | WARNING | Warnings that are generated by BigJob |
| 3 | INFO | Useful runtime information that is generated by BigJob |
| 4 | DEBUG | Debug message added to the code by the developers. (Lots of output) |
For example, if you want to see the debug messages that BigJob generates during program execution, you would set BIGJOB_VERBOSE to DEBUG before you run your program:
BIGJOB_VERBOSE=DEBUG python mysagaprog.py
BigJob utilizes a configuration file named bigjob.conf located in the root of the BigJob installation (e.g. :code:`$HOME/.bigjob/python/lib/python2.<PYTHON_MINOR_VERSION>/site-packages/BigJob-<BIGJOB_VERSION>-py2.X.egg/):
# logging.DEBUG, logging.INFO, logging.WARNING, logging.ERROR, logging.CRITICAL
logging.level=logging.INFO
The log level can also be set inside the BigJob script that you are running as follows:
import logging
from bigjob import logger
logger.setLevel(logging.FATAL)
Q: How can I control BigJob log messages from the application it is executing?
BigJob logger can be obtained and handlers can be added to the logger object. For example, with the below set of instructions, the application and BigJob debug messages are written to the namd_bigwork.log file:
logger = logging.getLogger('bigjob')
fileHandle = logging.FileHandler('namd_bigwork.log',mode='w')
fileHandle.setLevel(logging.DEBUG)
logger.addHandler(fileHandle)
logger.debug("Logging to namd_bigwork.log at DEBUG level")