Performance¶
structlog
’s default configuration tries to be as unsurprising and not confusing to new developers as possible.
Some of the choices made come with an avoidable performance price tag – although its impact is debatable.
Here are a few hints how to get most out of structlog
in production:
Use plain dicts as context classes. Python is full of them and they are highly optimized:
configure(context_class=dict)
If you don’t use automated parsing (you should!) and need predictable order of your keys for some reason, use the key_order argument of
KeyValueRenderer
.Use a specific wrapper class instead of the generic one.
structlog
comes with ones for the Standard Library Logging and for Twisted:configure(wrapper_class=structlog.stdlib.BoundLogger)
Writing own wrapper classes is straightforward too.
Avoid (frequently) calling log methods on loggers you get back from
structlog.wrap_logger()
andstructlog.get_logger()
. Since those functions are usually called in module scope and thus before you are able to configure them, they return a proxy that assembles the correct logger on demand.Create a local logger if you expect to log frequently without binding:
logger = structlog.get_logger() def f(): log = logger.bind() for i in range(1000000000): log.info("iterated", i=i)
Set the cache_logger_on_first_use option to True so the aforementioned on-demand loggers will be assembled only once and cached for future uses:
configure(cache_logger_on_first_use=True)
This has the only drawback is that later calls on
configure()
don’t have any effect on already cached loggers – that shouldn’t matter outside of testing though.Use a faster JSON serializer than the standard library. Possible alternatives are among others simplejson or RapidJSON (Python 3 only):
structlog.processors.JSONRenderer(serializer=rapidjson.dumps)