fix: limit the delay between tasks to 60s

lib/spark.js

@@ -211,10 +211,17 @@ export default class Spark {
         this.handleRunError(err)
       }
       const duration = Date.now() - started
-      const baseDelay = APPROX_ROUND_LENGTH_IN_MS / this.#tasker.maxTasksPerRound
-      const delay = baseDelay - duration
+      const delay = calculateDelayBeforeNextTask({
+        roundLengthInMs: APPROX_ROUND_LENGTH_IN_MS,
+        maxTasksPerRound: this.#tasker.maxTasksPerRound,
+        lastTaskDurationInMs: duration
+      })
+
       if (delay > 0) {
-        console.log('Sleeping for %s seconds before starting the next task...', Math.round(delay / 1000))
+        console.log(
+          'Sleeping for %s seconds before starting the next task...',
+          Math.round(delay / 1000)
+        )
         await sleep(delay)
         console.log() // add an empty line to visually delimit logs from different tasks
       }
@@ -231,6 +238,22 @@ export default class Spark {
   }
 }
 
+/**
+ * @param {object} args
+ * @param {number} args.roundLengthInMs
+ * @param {number} args.maxTasksPerRound
+ * @param {number} args.lastTaskDurationInMs
+ */
+export function calculateDelayBeforeNextTask ({
+  roundLengthInMs,
+  maxTasksPerRound,
+  lastTaskDurationInMs
+}) {
+  const baseDelay = roundLengthInMs / maxTasksPerRound
+  const delay = baseDelay - lastTaskDurationInMs
+  return Math.min(delay, 60_000)
+}
+
 export function newStats () {
   return {
     timeout: false,

test/spark.js

@@ -1,6 +1,6 @@
 /* global Zinnia */
 
-import Spark, { newStats } from '../lib/spark.js'
+import Spark, { calculateDelayBeforeNextTask, newStats } from '../lib/spark.js'
 import { test } from 'zinnia:test'
 import { assertInstanceOf, assertEquals, assertArrayIncludes } from 'zinnia:assert'
 import { SPARK_VERSION } from '../lib/constants.js'
@@ -271,3 +271,33 @@ test('submitRetrieval', async () => {
     }
   ])
 })
+
+test('calculateDelayBeforeNextTask() returns value based on average task duration', () => {
+  const delay = calculateDelayBeforeNextTask({
+    lastTaskDurationInMs: 3_000,
+
+    // one task every 10 seconds (on average)
+    roundLengthInMs: 60_000,
+    maxTasksPerRound: 6
+  })
+  assertEquals(delay, 7_000)
+})
+
+test('calculateDelayBeforeNextTask() handles zero tasks per round', () => {
+  const delay = calculateDelayBeforeNextTask({
+    maxTasksPerRound: 0,
+    // the values below are not important
+    roundLengthInMs: 12345,
+    lastTaskDurationInMs: 12
+  })
+  assertEquals(delay, 60_000)
+})
+
+test('calculateDelayBeforeNextTask() handles one task per round', () => {
+  const delay = calculateDelayBeforeNextTask({
+    roundLengthInMs: 20 * 60_000,
+    maxTasksPerRound: 1,
+    lastTaskDurationInMs: 1_000
+  })
+  assertEquals(delay, 60_000)
+})