Антон

window.onload = function () {
  fetch(url)
    .then((response) => {
      return response.json();
    })
    .then((req) => {
      var ctx = document.getElementById("myChart").getContext("2d");
      var old = [0, 25, 78, 67, 96, 92];
      // old.push(req)
      var chart = new Chart(ctx, {
        type: "line",
        data: {
          labels: ["+5s", "+5s", "+5s", "+5s", "+5s", "+5s", "+5s"],
          datasets: [
            {
              label: "Загрузка процессора",
              borderColor: "rgb(255, 99, 132)",
              data: old,
            },
          ],
        },
        // Configuration options go here
        options: {
          responsive: true,
        },
      });
      setInterval(() => {
        fetch(url)
          .then((response) => {
            return response.json();
          })
          .then((req) => {
            addValue(req);
          });
      }, 5000);

      function addValue(req) {
        chart.data.datasets[0].data.push(req);
        chart.data.labels.push("+5s");
        chart.update();
      }
    });
};