Here’s the configuration on my serverless.yml for the lambda:

  sendXXX:
    handler: functions/sendXXX/index.handler
    timeout: 55
    provisionedConcurrency: 1
    events:
      - schedule: rate(1 minute)

Here’s the relevant Cloudwatch log:

2024-06-25T11:50:32.134Z    START RequestId: c2cfe6d6-10d3-4520-8ef1-c82730103331 Version: 170
2024-06-25T11:50:35.698Z    START RequestId: 3e331a19-31d9-4342-af21-fe0e7e023c6e Version: 170
2024-06-25T11:50:37.443Z    END RequestId: c2cfe6d6-10d3-4520-8ef1-c82730103331
2024-06-25T11:50:37.443Z    REPORT RequestId: c2cfe6d6-10d3-4520-8ef1-c82730103331 Duration: 5309.22 ms Billed Duration: 5310 ms Memory Size: 512 MB Max Memory Used: 328 MB
2024-06-25T11:50:38.330Z    END RequestId: 3e331a19-31d9-4342-af21-fe0e7e023c6e

As you can see, the request c2cfe6d6-10d3-4520-8ef1-c82730103331 started at 11:50:32.134Z. I expect the next request to start around 11:51:32, but that’s starting only after 3 seconds (at 11:50:35.698Z). I wonder why it’s working like this.

I tried removing the provisionedConcurrency setting altogether and changing the rate(1 minute) schedule to cron(* * * * ? *) without success. Wham am I doing wrong?

Is it because the lambda is getting concurrently executed sometimes? If so, is there a way to stop that?