Can Cron cause the site to go down or DDos attack?

Yesterday I started running a cronjob [code below] on my server

('*/1 * * * *', 'api.cron.sync_with_elastic',['nginx-access-logs']) 

In the morning I got a message that my website is down. I was unable to even SSH, I switched off the server from dashboard my cloud provider has provided and then restarted it. Below is the metric of the website in the last 24 hrs. enter image description here

Is this a DDoS attack or cron has caused this issue?