Cold start metric for CR serivce

[dheerajpanyam]

Is there a way to setup a log based counter metric to detect CR cold starts? What would be the log message to parse if it is available out of the box?

[DamianS]

Hello @dheerajpanyam  ,Welcome on Google Cloud Community.

Unfortunately logs are not shows directly that container have been created or cold start has been observed. I found two logs entries which might help you count cold starts:

1. Hello from Cloud Run! The container started successfully and is listening for HTTP requests on $PORT

{
  "textPayload": "2024/06/11 07:21:12 Hello from Cloud Run! The container started successfully and is listening for HTTP requests on $PORT",
  "insertId": "6667fae8000ed26210cfe6f7",
  "resource": {
    "type": "cloud_run_revision",
    "labels": {
      "service_name": "cold-start",
      "revision_name": "cold-start-00001-klf",
      "project_id": "webaap-wordpress-load",
      "location": "us-central1",
      "configuration_name": "cold-start"
    }
  },
  "timestamp": "2024-06-11T07:21:12.971362Z",
  "labels": {
    "instanceId": "005b70877061811d26475bf28cb34ab59df21a9c17156de648376f26308db2011a208481dc9ec7f8db0002b57c42ab726057984d9f5e126f5fcdef6a5629e8f2"
  },
  "logName": "projects/webaap-wordpress-load/logs/run.googleapis.com%2Fstderr",
  "receiveTimestamp": "2024-06-11T07:21:12.978704723Z"
}

Following log entry indicates that a Cloud Run container named "cold-start-00001-klf" in this case within the "cold-start" service in this case  has successfully started and is ready to receive HTTP requests.

2. Default STARTUP TCP probe succeeded after 1 attempt for container "hello-1" on port 8080.

{
  "textPayload": "Default STARTUP TCP probe succeeded after 1 attempt for container \"hello-1\" on port 8080.",
  "insertId": "6667fae8000f153512cfa794",
  "resource": {
    "type": "cloud_run_revision",
    "labels": {
      "location": "us-central1",
      "project_id": "webaap-wordpress-load",
      "configuration_name": "cold-start",
      "service_name": "cold-start",
      "revision_name": "cold-start-00001-klf"
    }
  },
  "timestamp": "2024-06-11T07:21:12.988469Z",
  "severity": "INFO",
  "labels": {
    "instanceId": "005b70877061811d26475bf28cb34ab59df21a9c17156de648376f26308db2011a208481dc9ec7f8db0002b57c42ab726057984d9f5e126f5fcdef6a5629e8f2"
  },
  "logName": "projects/webaap-wordpress-load/logs/run.googleapis.com%2Fvarlog%2Fsystem",
  "receiveTimestamp": "2024-06-11T07:21:12.994636043Z"
}

 Log entry indicates that the startup TCP probe for the "hello-1" container in this case on port 8080 in the "cold-start" revision in this case of the "cold-start" service in this case successfully completed after one attempt.

I've tried to find also any metric, related with cold start, however without any luck,.

--
cheers,
DamianS
LinkedIn medium.com Cloudskillsboost

[maverickwhites]

Yes, you can set up a log-based counter metric to detect Cloud Run cold starts by parsing log messages containing the phrase "cold start."

[DamianS]

Hello @maverickwhites 
Show me query example or evidence screenshot please, as I cannot found any log entry with phrase "cold start". 

--
cheers,
DamianS
LinkedIn medium.com Cloudskillsboost

[dheerajpanyam]

I tried the following log query to look for coldstarts and it didn't return anything

resource.type = "cloud_run_revision"

resource.labels.service_name = "my-service-production"

resource.labels.location = "us-east1"

jsonPayload.message =~ "coldstart"

severity>=DEFAULT

[DamianS]

Yup, I didn't found any logs containing various word schema "coldstart" either.