1.5 KiB
1.5 KiB
Asynchronous Logging
Asynchronous logging enables the minimum overhead of Pino. Asynchronous logging works by buffering log messages and writing them in larger chunks.
const pino = require('pino')
const logger = pino(pino.destination({
dest: './my-file', // omit for stdout
minLength: 4096, // Buffer before writing
sync: false // Asynchronous logging
}))
It's always possible to turn on synchronous logging by passing sync: true.
In this mode of operation, log messages are directly written to the
output stream as the messages are generated with a blocking operation.
- See
pino.destination pino.destinationis implemented onsonic-boom⇗.
AWS Lambda
Asynchronous logging is disabled by default on AWS Lambda or any other environment
that modifies process.stdout. If forcefully turned on, we recommend calling dest.flushSync() at the end
of each function execution to avoid losing data.
Caveats
Asynchronous logging has a couple of important caveats:
- As opposed to the synchronous mode, there is not a one-to-one relationship between
calls to logging methods (e.g.
logger.info) and writes to a log file - There is a possibility of the most recently buffered log messages being lost in case of a system failure, e.g. a power cut.
See also: