lemmy exponential retry simulation

exponential-retry.js

function calc(base) {
  function retryDelaySeconds(retry) {
    return Math.pow(base, retry);
  }

  function timeToStr(sec) {
    sec = Math.round(sec);
    if (sec < 60) {
      return sec + "s";
    }
    if (sec < 3600) {
      return Math.floor(sec / 60) + "m " + (sec % 60) + "s";
    }
    return Math.floor(sec / 3600) + "h " + Math.floor((sec % 3600) / 60) + "m";
  }
  downtimeSeconds = [
    1 * 60,
    10 * 60,
    30 * 60,
    60 * 60,
    2 * 3600,
    3 * 3600,
    6 * 3600,
    12 * 3600,
    24 * 3600,
    48 * 3600,
    7 * 24 * 3600,
  ];

  let table = [];
  for (downtime of downtimeSeconds) {
    let retries = 0;
    let currentTime = 0;
    while (currentTime < downtime) {
      currentTime += retryDelaySeconds(retries);
      retries++;
    }
    table.push({
      "Instance Downtime": timeToStr(downtime),
      "Federation Resumed At": timeToStr(currentTime),
      "Total Retry Attempts": retries,
      /*retries2: Math.log(downtime)/Math.log(base)*/
    });
  }
  return jsonToHtmlTable(table);
}

function jsonToHtmlTable(json) {
  // input is an array of objects, the object keys are the column and the values the rows
  let table = "<table><tr>";
  for (let key of Object.keys(json[0])) {
    table += "<th>" + key + "</th>";
  }
  table += "</tr>";
  for (let row of json) {
    table += "<tr>";
    for (let key of Object.keys(row)) {
      table += "<td>" + row[key] + "</td>";
    }
    table += "</tr>";
  }
  table += "</table>";
  return table + "\n";
}
copy(calc(2) + calc(1.5) + calc(1.25));