[Bug]: Formatter runs on log call, even if log is not correct level

[cerpins]

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Slow formatter

The problem

My application has formatters, which are slow.
When I run my application with level=info to get rid of debug logs in production, I notice that the formatter is ran for those debug logs, causing a considerable performance hit - even though level is info.

Please let me know if there is a way to work around this, or am I just misunderstanding winston and formatters. Thanks!

Here is my profiler:

Here is my minimal-ish reproducible:

const winston = require('winston');

const logger = winston.createLogger({
  level: 'info',
  format: winston.format.combine(
    winston.format.json(),
    winston.format((input) => {
      let lagger = 0;
      for (let i = 0; i < 1000000000; i++) {
        lagger += 1;
      }
      return input;
    })()
  ),
  defaultMeta: { service: 'user-service' },
  transports: [
    new winston.transports.Console({
      format: winston.format.simple(),
    })
  ],
});

setInterval(() => {
  // I still see formatter for this log in profiler taking up some seconds
  logger.debug('Hello world!');
}, 1000);

What version of Winston presents the issue?

v3.13.0

What version of Node are you using?

v18.18.0

If this worked in a previous version of Winston, which was it?

No response

Minimum Working Example

Posted above

Additional information

No response