test: improve worker choice strategies options coverage
[poolifier.git] / tests / pools / selection-strategies / selection-strategies.test.js
index 7a67f6c4b628922db22a760de4d3f5bafc117fea..6091bf080f327a3218f53522fcfd1780ef543a70 100644 (file)
@@ -15,6 +15,7 @@ describe('Selection strategies test suite', () => {
     expect(WorkerChoiceStrategies.ROUND_ROBIN).toBe('ROUND_ROBIN')
     expect(WorkerChoiceStrategies.LEAST_USED).toBe('LEAST_USED')
     expect(WorkerChoiceStrategies.LEAST_BUSY).toBe('LEAST_BUSY')
+    expect(WorkerChoiceStrategies.LEAST_ELU).toBe('LEAST_ELU')
     expect(WorkerChoiceStrategies.FAIR_SHARE).toBe('FAIR_SHARE')
     expect(WorkerChoiceStrategies.WEIGHTED_ROUND_ROBIN).toBe(
       'WEIGHTED_ROUND_ROBIN'
@@ -97,7 +98,7 @@ describe('Selection strategies test suite', () => {
         expect(
           pool.workerChoiceStrategyContext.workerChoiceStrategies.get(
             workerChoiceStrategy
-          ).currentWorkerNodeId
+          ).nextWorkerNodeId
         ).toBe(0)
         expect(
           pool.workerChoiceStrategyContext.workerChoiceStrategies.get(
@@ -114,7 +115,31 @@ describe('Selection strategies test suite', () => {
     await pool.destroy()
   })
 
-  it('Verify ROUND_ROBIN strategy default tasks usage statistics requirements', async () => {
+  it('Verify ROUND_ROBIN strategy default policy', async () => {
+    const workerChoiceStrategy = WorkerChoiceStrategies.ROUND_ROBIN
+    let pool = new FixedThreadPool(
+      max,
+      './tests/worker-files/thread/testWorker.js',
+      { workerChoiceStrategy }
+    )
+    expect(pool.workerChoiceStrategyContext.getStrategyPolicy()).toStrictEqual({
+      useDynamicWorker: true
+    })
+    await pool.destroy()
+    pool = new DynamicThreadPool(
+      min,
+      max,
+      './tests/worker-files/thread/testWorker.js',
+      { workerChoiceStrategy }
+    )
+    expect(pool.workerChoiceStrategyContext.getStrategyPolicy()).toStrictEqual({
+      useDynamicWorker: true
+    })
+    // We need to clean up the resources after our test
+    await pool.destroy()
+  })
+
+  it('Verify ROUND_ROBIN strategy default tasks statistics requirements', async () => {
     const workerChoiceStrategy = WorkerChoiceStrategies.ROUND_ROBIN
     let pool = new FixedThreadPool(
       max,
@@ -124,13 +149,21 @@ describe('Selection strategies test suite', () => {
     expect(
       pool.workerChoiceStrategyContext.getTaskStatisticsRequirements()
     ).toStrictEqual({
-      runTime: false,
-      avgRunTime: false,
-      medRunTime: false,
-      waitTime: false,
-      avgWaitTime: false,
-      medWaitTime: false,
-      elu: false
+      runTime: {
+        aggregate: false,
+        average: false,
+        median: false
+      },
+      waitTime: {
+        aggregate: false,
+        average: false,
+        median: false
+      },
+      elu: {
+        aggregate: false,
+        average: false,
+        median: false
+      }
     })
     await pool.destroy()
     pool = new DynamicThreadPool(
@@ -142,13 +175,21 @@ describe('Selection strategies test suite', () => {
     expect(
       pool.workerChoiceStrategyContext.getTaskStatisticsRequirements()
     ).toStrictEqual({
-      runTime: false,
-      avgRunTime: false,
-      medRunTime: false,
-      waitTime: false,
-      avgWaitTime: false,
-      medWaitTime: false,
-      elu: false
+      runTime: {
+        aggregate: false,
+        average: false,
+        median: false
+      },
+      waitTime: {
+        aggregate: false,
+        average: false,
+        median: false
+      },
+      elu: {
+        aggregate: false,
+        average: false,
+        median: false
+      }
     })
     // We need to clean up the resources after our test
     await pool.destroy()
@@ -176,18 +217,32 @@ describe('Selection strategies test suite', () => {
           failed: 0
         },
         runTime: {
-          aggregation: 0,
+          aggregate: 0,
           average: 0,
           median: 0,
           history: expect.any(CircularArray)
         },
         waitTime: {
-          aggregation: 0,
+          aggregate: 0,
           average: 0,
           median: 0,
           history: expect.any(CircularArray)
         },
-        elu: undefined
+        elu: {
+          idle: {
+            aggregate: 0,
+            average: 0,
+            median: 0,
+            history: expect.any(CircularArray)
+          },
+          active: {
+            aggregate: 0,
+            average: 0,
+            median: 0,
+            history: expect.any(CircularArray)
+          },
+          utilization: 0
+        }
       })
     }
     expect(
@@ -222,18 +277,32 @@ describe('Selection strategies test suite', () => {
           failed: 0
         },
         runTime: {
-          aggregation: 0,
+          aggregate: 0,
           average: 0,
           median: 0,
           history: expect.any(CircularArray)
         },
         waitTime: {
-          aggregation: 0,
+          aggregate: 0,
           average: 0,
           median: 0,
           history: expect.any(CircularArray)
         },
-        elu: undefined
+        elu: {
+          idle: {
+            aggregate: 0,
+            average: 0,
+            median: 0,
+            history: expect.any(CircularArray)
+          },
+          active: {
+            aggregate: 0,
+            average: 0,
+            median: 0,
+            history: expect.any(CircularArray)
+          },
+          utilization: 0
+        }
       })
     }
     expect(
@@ -311,7 +380,31 @@ describe('Selection strategies test suite', () => {
     await pool.destroy()
   })
 
-  it('Verify LEAST_USED strategy default tasks usage statistics requirements', async () => {
+  it('Verify LEAST_USED strategy default policy', async () => {
+    const workerChoiceStrategy = WorkerChoiceStrategies.LEAST_USED
+    let pool = new FixedThreadPool(
+      max,
+      './tests/worker-files/thread/testWorker.js',
+      { workerChoiceStrategy }
+    )
+    expect(pool.workerChoiceStrategyContext.getStrategyPolicy()).toStrictEqual({
+      useDynamicWorker: false
+    })
+    await pool.destroy()
+    pool = new DynamicThreadPool(
+      min,
+      max,
+      './tests/worker-files/thread/testWorker.js',
+      { workerChoiceStrategy }
+    )
+    expect(pool.workerChoiceStrategyContext.getStrategyPolicy()).toStrictEqual({
+      useDynamicWorker: false
+    })
+    // We need to clean up the resources after our test
+    await pool.destroy()
+  })
+
+  it('Verify LEAST_USED strategy default tasks statistics requirements', async () => {
     const workerChoiceStrategy = WorkerChoiceStrategies.LEAST_USED
     let pool = new FixedThreadPool(
       max,
@@ -321,13 +414,21 @@ describe('Selection strategies test suite', () => {
     expect(
       pool.workerChoiceStrategyContext.getTaskStatisticsRequirements()
     ).toStrictEqual({
-      runTime: false,
-      avgRunTime: false,
-      medRunTime: false,
-      waitTime: false,
-      avgWaitTime: false,
-      medWaitTime: false,
-      elu: false
+      runTime: {
+        aggregate: false,
+        average: false,
+        median: false
+      },
+      waitTime: {
+        aggregate: false,
+        average: false,
+        median: false
+      },
+      elu: {
+        aggregate: false,
+        average: false,
+        median: false
+      }
     })
     await pool.destroy()
     pool = new DynamicThreadPool(
@@ -339,13 +440,21 @@ describe('Selection strategies test suite', () => {
     expect(
       pool.workerChoiceStrategyContext.getTaskStatisticsRequirements()
     ).toStrictEqual({
-      runTime: false,
-      avgRunTime: false,
-      medRunTime: false,
-      waitTime: false,
-      avgWaitTime: false,
-      medWaitTime: false,
-      elu: false
+      runTime: {
+        aggregate: false,
+        average: false,
+        median: false
+      },
+      waitTime: {
+        aggregate: false,
+        average: false,
+        median: false
+      },
+      elu: {
+        aggregate: false,
+        average: false,
+        median: false
+      }
     })
     // We need to clean up the resources after our test
     await pool.destroy()
@@ -367,25 +476,43 @@ describe('Selection strategies test suite', () => {
     for (const workerNode of pool.workerNodes) {
       expect(workerNode.workerUsage).toStrictEqual({
         tasks: {
-          executed: maxMultiplier,
+          executed: expect.any(Number),
           executing: 0,
           queued: 0,
           failed: 0
         },
         runTime: {
-          aggregation: 0,
+          aggregate: 0,
           average: 0,
           median: 0,
           history: expect.any(CircularArray)
         },
         waitTime: {
-          aggregation: 0,
+          aggregate: 0,
           average: 0,
           median: 0,
           history: expect.any(CircularArray)
         },
-        elu: undefined
+        elu: {
+          idle: {
+            aggregate: 0,
+            average: 0,
+            median: 0,
+            history: expect.any(CircularArray)
+          },
+          active: {
+            aggregate: 0,
+            average: 0,
+            median: 0,
+            history: expect.any(CircularArray)
+          },
+          utilization: 0
+        }
       })
+      expect(workerNode.workerUsage.tasks.executed).toBeGreaterThanOrEqual(0)
+      expect(workerNode.workerUsage.tasks.executed).toBeLessThanOrEqual(
+        max * maxMultiplier
+      )
     }
     // We need to clean up the resources after our test
     await pool.destroy()
@@ -408,32 +535,73 @@ describe('Selection strategies test suite', () => {
     for (const workerNode of pool.workerNodes) {
       expect(workerNode.workerUsage).toStrictEqual({
         tasks: {
-          executed: maxMultiplier,
+          executed: expect.any(Number),
           executing: 0,
           queued: 0,
           failed: 0
         },
         runTime: {
-          aggregation: 0,
+          aggregate: 0,
           average: 0,
           median: 0,
           history: expect.any(CircularArray)
         },
         waitTime: {
-          aggregation: 0,
+          aggregate: 0,
           average: 0,
           median: 0,
           history: expect.any(CircularArray)
         },
-
-        elu: undefined
+        elu: {
+          idle: {
+            aggregate: 0,
+            average: 0,
+            median: 0,
+            history: expect.any(CircularArray)
+          },
+          active: {
+            aggregate: 0,
+            average: 0,
+            median: 0,
+            history: expect.any(CircularArray)
+          },
+          utilization: 0
+        }
       })
+      expect(workerNode.workerUsage.tasks.executed).toBeGreaterThanOrEqual(0)
+      expect(workerNode.workerUsage.tasks.executed).toBeLessThanOrEqual(
+        max * maxMultiplier
+      )
     }
     // We need to clean up the resources after our test
     await pool.destroy()
   })
 
-  it('Verify LEAST_BUSY strategy default tasks usage statistics requirements', async () => {
+  it('Verify LEAST_BUSY strategy default policy', async () => {
+    const workerChoiceStrategy = WorkerChoiceStrategies.LEAST_BUSY
+    let pool = new FixedThreadPool(
+      max,
+      './tests/worker-files/thread/testWorker.js',
+      { workerChoiceStrategy }
+    )
+    expect(pool.workerChoiceStrategyContext.getStrategyPolicy()).toStrictEqual({
+      useDynamicWorker: false
+    })
+    await pool.destroy()
+    pool = new DynamicThreadPool(
+      min,
+      max,
+      './tests/worker-files/thread/testWorker.js',
+      { workerChoiceStrategy }
+    )
+    expect(pool.workerChoiceStrategyContext.getStrategyPolicy()).toStrictEqual({
+      useDynamicWorker: false
+    })
+    // We need to clean up the resources after our test
+    await pool.destroy()
+  })
+
+  it('Verify LEAST_BUSY strategy default tasks statistics requirements', async () => {
     const workerChoiceStrategy = WorkerChoiceStrategies.LEAST_BUSY
     let pool = new FixedThreadPool(
       max,
@@ -443,13 +611,21 @@ describe('Selection strategies test suite', () => {
     expect(
       pool.workerChoiceStrategyContext.getTaskStatisticsRequirements()
     ).toStrictEqual({
-      runTime: true,
-      avgRunTime: false,
-      medRunTime: false,
-      waitTime: false,
-      avgWaitTime: false,
-      medWaitTime: false,
-      elu: false
+      runTime: {
+        aggregate: true,
+        average: false,
+        median: false
+      },
+      waitTime: {
+        aggregate: true,
+        average: false,
+        median: false
+      },
+      elu: {
+        aggregate: false,
+        average: false,
+        median: false
+      }
     })
     await pool.destroy()
     pool = new DynamicThreadPool(
@@ -461,13 +637,21 @@ describe('Selection strategies test suite', () => {
     expect(
       pool.workerChoiceStrategyContext.getTaskStatisticsRequirements()
     ).toStrictEqual({
-      runTime: true,
-      avgRunTime: false,
-      medRunTime: false,
-      waitTime: false,
-      avgWaitTime: false,
-      medWaitTime: false,
-      elu: false
+      runTime: {
+        aggregate: true,
+        average: false,
+        median: false
+      },
+      waitTime: {
+        aggregate: true,
+        average: false,
+        median: false
+      },
+      elu: {
+        aggregate: false,
+        average: false,
+        median: false
+      }
     })
     // We need to clean up the resources after our test
     await pool.destroy()
@@ -495,24 +679,39 @@ describe('Selection strategies test suite', () => {
           failed: 0
         },
         runTime: {
-          aggregation: expect.any(Number),
+          aggregate: expect.any(Number),
           average: 0,
           median: 0,
           history: expect.any(CircularArray)
         },
         waitTime: {
-          aggregation: 0,
+          aggregate: expect.any(Number),
           average: 0,
           median: 0,
           history: expect.any(CircularArray)
         },
-        elu: undefined
+        elu: {
+          idle: {
+            aggregate: 0,
+            average: 0,
+            median: 0,
+            history: expect.any(CircularArray)
+          },
+          active: {
+            aggregate: 0,
+            average: 0,
+            median: 0,
+            history: expect.any(CircularArray)
+          },
+          utilization: 0
+        }
       })
       expect(workerNode.workerUsage.tasks.executed).toBeGreaterThanOrEqual(0)
       expect(workerNode.workerUsage.tasks.executed).toBeLessThanOrEqual(
         max * maxMultiplier
       )
-      expect(workerNode.workerUsage.runTime.aggregation).toBeGreaterThanOrEqual(
+      expect(workerNode.workerUsage.runTime.aggregate).toBeGreaterThanOrEqual(0)
+      expect(workerNode.workerUsage.waitTime.aggregate).toBeGreaterThanOrEqual(
         0
       )
     }
@@ -543,30 +742,272 @@ describe('Selection strategies test suite', () => {
           failed: 0
         },
         runTime: {
-          aggregation: expect.any(Number),
+          aggregate: expect.any(Number),
+          average: 0,
+          median: 0,
+          history: expect.any(CircularArray)
+        },
+        waitTime: {
+          aggregate: expect.any(Number),
+          average: 0,
+          median: 0,
+          history: expect.any(CircularArray)
+        },
+        elu: {
+          idle: {
+            aggregate: 0,
+            average: 0,
+            median: 0,
+            history: expect.any(CircularArray)
+          },
+          active: {
+            aggregate: 0,
+            average: 0,
+            median: 0,
+            history: expect.any(CircularArray)
+          },
+          utilization: 0
+        }
+      })
+      expect(workerNode.workerUsage.tasks.executed).toBeGreaterThanOrEqual(0)
+      expect(workerNode.workerUsage.tasks.executed).toBeLessThanOrEqual(
+        max * maxMultiplier
+      )
+      expect(workerNode.workerUsage.runTime.aggregate).toBeGreaterThanOrEqual(0)
+      expect(workerNode.workerUsage.waitTime.aggregate).toBeGreaterThanOrEqual(
+        0
+      )
+    }
+    // We need to clean up the resources after our test
+    await pool.destroy()
+  })
+
+  it('Verify LEAST_ELU strategy default policy', async () => {
+    const workerChoiceStrategy = WorkerChoiceStrategies.LEAST_ELU
+    let pool = new FixedThreadPool(
+      max,
+      './tests/worker-files/thread/testWorker.js',
+      { workerChoiceStrategy }
+    )
+    expect(pool.workerChoiceStrategyContext.getStrategyPolicy()).toStrictEqual({
+      useDynamicWorker: false
+    })
+    await pool.destroy()
+    pool = new DynamicThreadPool(
+      min,
+      max,
+      './tests/worker-files/thread/testWorker.js',
+      { workerChoiceStrategy }
+    )
+    expect(pool.workerChoiceStrategyContext.getStrategyPolicy()).toStrictEqual({
+      useDynamicWorker: false
+    })
+    // We need to clean up the resources after our test
+    await pool.destroy()
+  })
+
+  it('Verify LEAST_ELU strategy default tasks statistics requirements', async () => {
+    const workerChoiceStrategy = WorkerChoiceStrategies.LEAST_ELU
+    let pool = new FixedThreadPool(
+      max,
+      './tests/worker-files/thread/testWorker.js',
+      { workerChoiceStrategy }
+    )
+    expect(
+      pool.workerChoiceStrategyContext.getTaskStatisticsRequirements()
+    ).toStrictEqual({
+      runTime: {
+        aggregate: false,
+        average: false,
+        median: false
+      },
+      waitTime: {
+        aggregate: false,
+        average: false,
+        median: false
+      },
+      elu: {
+        aggregate: true,
+        average: false,
+        median: false
+      }
+    })
+    await pool.destroy()
+    pool = new DynamicThreadPool(
+      min,
+      max,
+      './tests/worker-files/thread/testWorker.js',
+      { workerChoiceStrategy }
+    )
+    expect(
+      pool.workerChoiceStrategyContext.getTaskStatisticsRequirements()
+    ).toStrictEqual({
+      runTime: {
+        aggregate: false,
+        average: false,
+        median: false
+      },
+      waitTime: {
+        aggregate: false,
+        average: false,
+        median: false
+      },
+      elu: {
+        aggregate: true,
+        average: false,
+        median: false
+      }
+    })
+    // We need to clean up the resources after our test
+    await pool.destroy()
+  })
+
+  it('Verify LEAST_ELU strategy can be run in a fixed pool', async () => {
+    const pool = new FixedThreadPool(
+      max,
+      './tests/worker-files/thread/testWorker.js',
+      { workerChoiceStrategy: WorkerChoiceStrategies.LEAST_ELU }
+    )
+    // TODO: Create a better test to cover `LeastEluWorkerChoiceStrategy#choose`
+    const promises = new Set()
+    const maxMultiplier = 2
+    for (let i = 0; i < max * maxMultiplier; i++) {
+      promises.add(pool.execute())
+    }
+    await Promise.all(promises)
+    for (const workerNode of pool.workerNodes) {
+      expect(workerNode.workerUsage).toStrictEqual({
+        tasks: {
+          executed: expect.any(Number),
+          executing: 0,
+          queued: 0,
+          failed: 0
+        },
+        runTime: {
+          aggregate: 0,
+          average: 0,
+          median: 0,
+          history: expect.any(CircularArray)
+        },
+        waitTime: {
+          aggregate: 0,
+          average: 0,
+          median: 0,
+          history: expect.any(CircularArray)
+        },
+        elu: {
+          idle: {
+            aggregate: 0,
+            average: 0,
+            median: 0,
+            history: expect.any(CircularArray)
+          },
+          active: {
+            aggregate: expect.any(Number),
+            average: 0,
+            median: 0,
+            history: expect.any(CircularArray)
+          },
+          utilization: expect.any(Number)
+        }
+      })
+      expect(workerNode.workerUsage.tasks.executed).toBeGreaterThanOrEqual(0)
+      expect(workerNode.workerUsage.tasks.executed).toBeLessThanOrEqual(
+        max * maxMultiplier
+      )
+      expect(workerNode.workerUsage.elu.utilization).toBeGreaterThanOrEqual(0)
+      expect(workerNode.workerUsage.elu.utilization).toBeLessThanOrEqual(1)
+    }
+    // We need to clean up the resources after our test
+    await pool.destroy()
+  })
+
+  it('Verify LEAST_ELU strategy can be run in a dynamic pool', async () => {
+    const pool = new DynamicThreadPool(
+      min,
+      max,
+      './tests/worker-files/thread/testWorker.js',
+      { workerChoiceStrategy: WorkerChoiceStrategies.LEAST_ELU }
+    )
+    // TODO: Create a better test to cover `LeastEluWorkerChoiceStrategy#choose`
+    const promises = new Set()
+    const maxMultiplier = 2
+    for (let i = 0; i < max * maxMultiplier; i++) {
+      promises.add(pool.execute())
+    }
+    await Promise.all(promises)
+    for (const workerNode of pool.workerNodes) {
+      expect(workerNode.workerUsage).toStrictEqual({
+        tasks: {
+          executed: expect.any(Number),
+          executing: 0,
+          queued: 0,
+          failed: 0
+        },
+        runTime: {
+          aggregate: 0,
           average: 0,
           median: 0,
           history: expect.any(CircularArray)
         },
         waitTime: {
-          aggregation: 0,
+          aggregate: 0,
           average: 0,
           median: 0,
           history: expect.any(CircularArray)
         },
-        elu: undefined
+        elu: {
+          idle: {
+            aggregate: 0,
+            average: 0,
+            median: 0,
+            history: expect.any(CircularArray)
+          },
+          active: {
+            aggregate: expect.any(Number),
+            average: 0,
+            median: 0,
+            history: expect.any(CircularArray)
+          },
+          utilization: expect.any(Number)
+        }
       })
-      expect(workerNode.workerUsage.tasks.executed).toBeGreaterThan(0)
+      expect(workerNode.workerUsage.tasks.executed).toBeGreaterThanOrEqual(0)
       expect(workerNode.workerUsage.tasks.executed).toBeLessThanOrEqual(
         max * maxMultiplier
       )
-      expect(workerNode.workerUsage.runTime.aggregation).toBeGreaterThan(0)
+      expect(workerNode.workerUsage.elu.utilization).toBeGreaterThanOrEqual(0)
+      expect(workerNode.workerUsage.elu.utilization).toBeLessThanOrEqual(1)
     }
     // We need to clean up the resources after our test
     await pool.destroy()
   })
 
-  it('Verify FAIR_SHARE strategy default tasks usage statistics requirements', async () => {
+  it('Verify FAIR_SHARE strategy default policy', async () => {
+    const workerChoiceStrategy = WorkerChoiceStrategies.FAIR_SHARE
+    let pool = new FixedThreadPool(
+      max,
+      './tests/worker-files/thread/testWorker.js',
+      { workerChoiceStrategy }
+    )
+    expect(pool.workerChoiceStrategyContext.getStrategyPolicy()).toStrictEqual({
+      useDynamicWorker: false
+    })
+    await pool.destroy()
+    pool = new DynamicThreadPool(
+      min,
+      max,
+      './tests/worker-files/thread/testWorker.js',
+      { workerChoiceStrategy }
+    )
+    expect(pool.workerChoiceStrategyContext.getStrategyPolicy()).toStrictEqual({
+      useDynamicWorker: false
+    })
+    // We need to clean up the resources after our test
+    await pool.destroy()
+  })
+
+  it('Verify FAIR_SHARE strategy default tasks statistics requirements', async () => {
     const workerChoiceStrategy = WorkerChoiceStrategies.FAIR_SHARE
     let pool = new FixedThreadPool(
       max,
@@ -576,13 +1017,21 @@ describe('Selection strategies test suite', () => {
     expect(
       pool.workerChoiceStrategyContext.getTaskStatisticsRequirements()
     ).toStrictEqual({
-      runTime: true,
-      avgRunTime: true,
-      medRunTime: false,
-      waitTime: false,
-      avgWaitTime: false,
-      medWaitTime: false,
-      elu: false
+      runTime: {
+        aggregate: true,
+        average: true,
+        median: false
+      },
+      waitTime: {
+        aggregate: false,
+        average: false,
+        median: false
+      },
+      elu: {
+        aggregate: true,
+        average: true,
+        median: false
+      }
     })
     await pool.destroy()
     pool = new DynamicThreadPool(
@@ -594,13 +1043,21 @@ describe('Selection strategies test suite', () => {
     expect(
       pool.workerChoiceStrategyContext.getTaskStatisticsRequirements()
     ).toStrictEqual({
-      runTime: true,
-      avgRunTime: true,
-      medRunTime: false,
-      waitTime: false,
-      avgWaitTime: false,
-      medWaitTime: false,
-      elu: false
+      runTime: {
+        aggregate: true,
+        average: true,
+        median: false
+      },
+      waitTime: {
+        aggregate: false,
+        average: false,
+        median: false
+      },
+      elu: {
+        aggregate: true,
+        average: true,
+        median: false
+      }
     })
     // We need to clean up the resources after our test
     await pool.destroy()
@@ -622,27 +1079,47 @@ describe('Selection strategies test suite', () => {
     for (const workerNode of pool.workerNodes) {
       expect(workerNode.workerUsage).toStrictEqual({
         tasks: {
-          executed: maxMultiplier,
+          executed: expect.any(Number),
           executing: 0,
           queued: 0,
           failed: 0
         },
         runTime: {
-          aggregation: expect.any(Number),
+          aggregate: expect.any(Number),
           average: expect.any(Number),
           median: 0,
           history: expect.any(CircularArray)
         },
         waitTime: {
-          aggregation: 0,
+          aggregate: 0,
           average: 0,
           median: 0,
           history: expect.any(CircularArray)
         },
-        elu: undefined
+        elu: {
+          idle: {
+            aggregate: 0,
+            average: 0,
+            median: 0,
+            history: expect.any(CircularArray)
+          },
+          active: {
+            aggregate: expect.any(Number),
+            average: expect.any(Number),
+            median: 0,
+            history: expect.any(CircularArray)
+          },
+          utilization: expect.any(Number)
+        }
       })
-      expect(workerNode.workerUsage.runTime.aggregation).toBeGreaterThan(0)
-      expect(workerNode.workerUsage.runTime.average).toBeGreaterThan(0)
+      expect(workerNode.workerUsage.tasks.executed).toBeGreaterThanOrEqual(0)
+      expect(workerNode.workerUsage.tasks.executed).toBeLessThanOrEqual(
+        max * maxMultiplier
+      )
+      expect(workerNode.workerUsage.runTime.aggregate).toBeGreaterThanOrEqual(0)
+      expect(workerNode.workerUsage.runTime.average).toBeGreaterThanOrEqual(0)
+      expect(workerNode.workerUsage.elu.utilization).toBeGreaterThanOrEqual(0)
+      expect(workerNode.workerUsage.elu.utilization).toBeLessThanOrEqual(1)
     }
     expect(
       pool.workerChoiceStrategyContext.workerChoiceStrategies.get(
@@ -670,27 +1147,47 @@ describe('Selection strategies test suite', () => {
     for (const workerNode of pool.workerNodes) {
       expect(workerNode.workerUsage).toStrictEqual({
         tasks: {
-          executed: maxMultiplier,
+          executed: expect.any(Number),
           executing: 0,
           queued: 0,
           failed: 0
         },
         runTime: {
-          aggregation: expect.any(Number),
+          aggregate: expect.any(Number),
           average: expect.any(Number),
           median: 0,
           history: expect.any(CircularArray)
         },
         waitTime: {
-          aggregation: 0,
+          aggregate: 0,
           average: 0,
           median: 0,
           history: expect.any(CircularArray)
         },
-        elu: undefined
+        elu: {
+          idle: {
+            aggregate: 0,
+            average: 0,
+            median: 0,
+            history: expect.any(CircularArray)
+          },
+          active: {
+            aggregate: expect.any(Number),
+            average: expect.any(Number),
+            median: 0,
+            history: expect.any(CircularArray)
+          },
+          utilization: expect.any(Number)
+        }
       })
-      expect(workerNode.workerUsage.runTime.aggregation).toBeGreaterThan(0)
-      expect(workerNode.workerUsage.runTime.average).toBeGreaterThan(0)
+      expect(workerNode.workerUsage.tasks.executed).toBeGreaterThanOrEqual(0)
+      expect(workerNode.workerUsage.tasks.executed).toBeLessThanOrEqual(
+        max * maxMultiplier
+      )
+      expect(workerNode.workerUsage.runTime.aggregate).toBeGreaterThanOrEqual(0)
+      expect(workerNode.workerUsage.runTime.average).toBeGreaterThanOrEqual(0)
+      expect(workerNode.workerUsage.elu.utilization).toBeGreaterThanOrEqual(0)
+      expect(workerNode.workerUsage.elu.utilization).toBeLessThanOrEqual(1)
     }
     expect(
       pool.workerChoiceStrategyContext.workerChoiceStrategies.get(
@@ -709,7 +1206,7 @@ describe('Selection strategies test suite', () => {
       {
         workerChoiceStrategy: WorkerChoiceStrategies.FAIR_SHARE,
         workerChoiceStrategyOptions: {
-          medRunTime: true
+          runTime: { median: true }
         }
       }
     )
@@ -723,27 +1220,47 @@ describe('Selection strategies test suite', () => {
     for (const workerNode of pool.workerNodes) {
       expect(workerNode.workerUsage).toStrictEqual({
         tasks: {
-          executed: maxMultiplier,
+          executed: expect.any(Number),
           executing: 0,
           queued: 0,
           failed: 0
         },
         runTime: {
-          aggregation: expect.any(Number),
+          aggregate: expect.any(Number),
           average: 0,
           median: expect.any(Number),
           history: expect.any(CircularArray)
         },
         waitTime: {
-          aggregation: 0,
+          aggregate: 0,
           average: 0,
           median: 0,
           history: expect.any(CircularArray)
         },
-        elu: undefined
+        elu: {
+          idle: {
+            aggregate: 0,
+            average: 0,
+            median: 0,
+            history: expect.any(CircularArray)
+          },
+          active: {
+            aggregate: expect.any(Number),
+            average: expect.any(Number),
+            median: 0,
+            history: expect.any(CircularArray)
+          },
+          utilization: expect.any(Number)
+        }
       })
-      expect(workerNode.workerUsage.runTime.aggregation).toBeGreaterThan(0)
-      expect(workerNode.workerUsage.runTime.median).toBeGreaterThan(0)
+      expect(workerNode.workerUsage.tasks.executed).toBeGreaterThanOrEqual(0)
+      expect(workerNode.workerUsage.tasks.executed).toBeLessThanOrEqual(
+        max * maxMultiplier
+      )
+      expect(workerNode.workerUsage.runTime.aggregate).toBeGreaterThanOrEqual(0)
+      expect(workerNode.workerUsage.runTime.median).toBeGreaterThanOrEqual(0)
+      expect(workerNode.workerUsage.elu.utilization).toBeGreaterThanOrEqual(0)
+      expect(workerNode.workerUsage.elu.utilization).toBeLessThanOrEqual(1)
     }
     expect(
       pool.workerChoiceStrategyContext.workerChoiceStrategies.get(
@@ -828,7 +1345,31 @@ describe('Selection strategies test suite', () => {
     await pool.destroy()
   })
 
-  it('Verify WEIGHTED_ROUND_ROBIN strategy default tasks usage statistics requirements', async () => {
+  it('Verify WEIGHTED_ROUND_ROBIN strategy default policy', async () => {
+    const workerChoiceStrategy = WorkerChoiceStrategies.WEIGHTED_ROUND_ROBIN
+    let pool = new FixedThreadPool(
+      max,
+      './tests/worker-files/thread/testWorker.js',
+      { workerChoiceStrategy }
+    )
+    expect(pool.workerChoiceStrategyContext.getStrategyPolicy()).toStrictEqual({
+      useDynamicWorker: true
+    })
+    await pool.destroy()
+    pool = new DynamicThreadPool(
+      min,
+      max,
+      './tests/worker-files/thread/testWorker.js',
+      { workerChoiceStrategy }
+    )
+    expect(pool.workerChoiceStrategyContext.getStrategyPolicy()).toStrictEqual({
+      useDynamicWorker: true
+    })
+    // We need to clean up the resources after our test
+    await pool.destroy()
+  })
+
+  it('Verify WEIGHTED_ROUND_ROBIN strategy default tasks statistics requirements', async () => {
     const workerChoiceStrategy = WorkerChoiceStrategies.WEIGHTED_ROUND_ROBIN
     let pool = new FixedThreadPool(
       max,
@@ -838,13 +1379,21 @@ describe('Selection strategies test suite', () => {
     expect(
       pool.workerChoiceStrategyContext.getTaskStatisticsRequirements()
     ).toStrictEqual({
-      runTime: true,
-      avgRunTime: true,
-      medRunTime: false,
-      waitTime: false,
-      avgWaitTime: false,
-      medWaitTime: false,
-      elu: false
+      runTime: {
+        aggregate: true,
+        average: true,
+        median: false
+      },
+      waitTime: {
+        aggregate: false,
+        average: false,
+        median: false
+      },
+      elu: {
+        aggregate: false,
+        average: false,
+        median: false
+      }
     })
     await pool.destroy()
     pool = new DynamicThreadPool(
@@ -856,13 +1405,21 @@ describe('Selection strategies test suite', () => {
     expect(
       pool.workerChoiceStrategyContext.getTaskStatisticsRequirements()
     ).toStrictEqual({
-      runTime: true,
-      avgRunTime: true,
-      medRunTime: false,
-      waitTime: false,
-      avgWaitTime: false,
-      medWaitTime: false,
-      elu: false
+      runTime: {
+        aggregate: true,
+        average: true,
+        median: false
+      },
+      waitTime: {
+        aggregate: false,
+        average: false,
+        median: false
+      },
+      elu: {
+        aggregate: false,
+        average: false,
+        median: false
+      }
     })
     // We need to clean up the resources after our test
     await pool.destroy()
@@ -890,26 +1447,38 @@ describe('Selection strategies test suite', () => {
           failed: 0
         },
         runTime: {
-          aggregation: expect.any(Number),
+          aggregate: expect.any(Number),
           average: expect.any(Number),
           median: 0,
           history: expect.any(CircularArray)
         },
         waitTime: {
-          aggregation: 0,
+          aggregate: 0,
           average: 0,
           median: 0,
           history: expect.any(CircularArray)
         },
-        elu: undefined
+        elu: {
+          idle: {
+            aggregate: 0,
+            average: 0,
+            median: 0,
+            history: expect.any(CircularArray)
+          },
+          active: {
+            aggregate: 0,
+            average: 0,
+            median: 0,
+            history: expect.any(CircularArray)
+          },
+          utilization: 0
+        }
       })
       expect(workerNode.workerUsage.tasks.executed).toBeGreaterThanOrEqual(0)
       expect(workerNode.workerUsage.tasks.executed).toBeLessThanOrEqual(
         max * maxMultiplier
       )
-      expect(workerNode.workerUsage.runTime.aggregation).toBeGreaterThanOrEqual(
-        0
-      )
+      expect(workerNode.workerUsage.runTime.aggregate).toBeGreaterThanOrEqual(0)
       expect(workerNode.workerUsage.runTime.average).toBeGreaterThanOrEqual(0)
     }
     expect(
@@ -949,24 +1518,38 @@ describe('Selection strategies test suite', () => {
           failed: 0
         },
         runTime: {
-          aggregation: expect.any(Number),
+          aggregate: expect.any(Number),
           average: expect.any(Number),
           median: 0,
           history: expect.any(CircularArray)
         },
         waitTime: {
-          aggregation: 0,
+          aggregate: 0,
           average: 0,
           median: 0,
           history: expect.any(CircularArray)
         },
-        elu: undefined
+        elu: {
+          idle: {
+            aggregate: 0,
+            average: 0,
+            median: 0,
+            history: expect.any(CircularArray)
+          },
+          active: {
+            aggregate: 0,
+            average: 0,
+            median: 0,
+            history: expect.any(CircularArray)
+          },
+          utilization: 0
+        }
       })
-      expect(workerNode.workerUsage.tasks.executed).toBeGreaterThan(0)
+      expect(workerNode.workerUsage.tasks.executed).toBeGreaterThanOrEqual(0)
       expect(workerNode.workerUsage.tasks.executed).toBeLessThanOrEqual(
         max * maxMultiplier
       )
-      expect(workerNode.workerUsage.runTime.aggregation).toBeGreaterThan(0)
+      expect(workerNode.workerUsage.runTime.aggregate).toBeGreaterThan(0)
       expect(workerNode.workerUsage.runTime.average).toBeGreaterThan(0)
     }
     expect(
@@ -991,7 +1574,7 @@ describe('Selection strategies test suite', () => {
       {
         workerChoiceStrategy: WorkerChoiceStrategies.WEIGHTED_ROUND_ROBIN,
         workerChoiceStrategyOptions: {
-          medRunTime: true
+          runTime: { median: true }
         }
       }
     )
@@ -1011,24 +1594,38 @@ describe('Selection strategies test suite', () => {
           failed: 0
         },
         runTime: {
-          aggregation: expect.any(Number),
+          aggregate: expect.any(Number),
           average: 0,
           median: expect.any(Number),
           history: expect.any(CircularArray)
         },
         waitTime: {
-          aggregation: 0,
+          aggregate: 0,
           average: 0,
           median: 0,
           history: expect.any(CircularArray)
         },
-        elu: undefined
+        elu: {
+          idle: {
+            aggregate: 0,
+            average: 0,
+            median: 0,
+            history: expect.any(CircularArray)
+          },
+          active: {
+            aggregate: 0,
+            average: 0,
+            median: 0,
+            history: expect.any(CircularArray)
+          },
+          utilization: 0
+        }
       })
-      expect(workerNode.workerUsage.tasks.executed).toBeGreaterThan(0)
+      expect(workerNode.workerUsage.tasks.executed).toBeGreaterThanOrEqual(0)
       expect(workerNode.workerUsage.tasks.executed).toBeLessThanOrEqual(
         max * maxMultiplier
       )
-      expect(workerNode.workerUsage.runTime.aggregation).toBeGreaterThan(0)
+      expect(workerNode.workerUsage.runTime.aggregate).toBeGreaterThan(0)
       expect(workerNode.workerUsage.runTime.median).toBeGreaterThan(0)
     }
     expect(
@@ -1054,7 +1651,7 @@ describe('Selection strategies test suite', () => {
     expect(
       pool.workerChoiceStrategyContext.workerChoiceStrategies.get(
         workerChoiceStrategy
-      ).currentWorkerNodeId
+      ).nextWorkerNodeId
     ).toBeDefined()
     expect(
       pool.workerChoiceStrategyContext.workerChoiceStrategies.get(
@@ -1070,7 +1667,7 @@ describe('Selection strategies test suite', () => {
     expect(
       pool.workerChoiceStrategyContext.workerChoiceStrategies.get(
         pool.workerChoiceStrategyContext.workerChoiceStrategy
-      ).currentWorkerNodeId
+      ).nextWorkerNodeId
     ).toBe(0)
     expect(
       pool.workerChoiceStrategyContext.workerChoiceStrategies.get(
@@ -1091,7 +1688,7 @@ describe('Selection strategies test suite', () => {
     expect(
       pool.workerChoiceStrategyContext.workerChoiceStrategies.get(
         workerChoiceStrategy
-      ).currentWorkerNodeId
+      ).nextWorkerNodeId
     ).toBeDefined()
     expect(
       pool.workerChoiceStrategyContext.workerChoiceStrategies.get(
@@ -1107,7 +1704,7 @@ describe('Selection strategies test suite', () => {
     expect(
       pool.workerChoiceStrategyContext.workerChoiceStrategies.get(
         pool.workerChoiceStrategyContext.workerChoiceStrategy
-      ).currentWorkerNodeId
+      ).nextWorkerNodeId
     ).toBe(0)
     expect(
       pool.workerChoiceStrategyContext.workerChoiceStrategies.get(
@@ -1123,7 +1720,32 @@ describe('Selection strategies test suite', () => {
     await pool.destroy()
   })
 
-  it('Verify INTERLEAVED_WEIGHTED_ROUND_ROBIN strategy default tasks usage statistics requirements', async () => {
+  it('Verify INTERLEAVED_WEIGHTED_ROUND_ROBIN strategy default policy', async () => {
+    const workerChoiceStrategy =
+      WorkerChoiceStrategies.INTERLEAVED_WEIGHTED_ROUND_ROBIN
+    let pool = new FixedThreadPool(
+      max,
+      './tests/worker-files/thread/testWorker.js',
+      { workerChoiceStrategy }
+    )
+    expect(pool.workerChoiceStrategyContext.getStrategyPolicy()).toStrictEqual({
+      useDynamicWorker: true
+    })
+    await pool.destroy()
+    pool = new DynamicThreadPool(
+      min,
+      max,
+      './tests/worker-files/thread/testWorker.js',
+      { workerChoiceStrategy }
+    )
+    expect(pool.workerChoiceStrategyContext.getStrategyPolicy()).toStrictEqual({
+      useDynamicWorker: true
+    })
+    // We need to clean up the resources after our test
+    await pool.destroy()
+  })
+
+  it('Verify INTERLEAVED_WEIGHTED_ROUND_ROBIN strategy default tasks statistics requirements', async () => {
     const workerChoiceStrategy =
       WorkerChoiceStrategies.INTERLEAVED_WEIGHTED_ROUND_ROBIN
     let pool = new FixedThreadPool(
@@ -1134,13 +1756,21 @@ describe('Selection strategies test suite', () => {
     expect(
       pool.workerChoiceStrategyContext.getTaskStatisticsRequirements()
     ).toStrictEqual({
-      runTime: false,
-      avgRunTime: false,
-      medRunTime: false,
-      waitTime: false,
-      avgWaitTime: false,
-      medWaitTime: false,
-      elu: false
+      runTime: {
+        aggregate: false,
+        average: false,
+        median: false
+      },
+      waitTime: {
+        aggregate: false,
+        average: false,
+        median: false
+      },
+      elu: {
+        aggregate: false,
+        average: false,
+        median: false
+      }
     })
     await pool.destroy()
     pool = new DynamicThreadPool(
@@ -1152,13 +1782,21 @@ describe('Selection strategies test suite', () => {
     expect(
       pool.workerChoiceStrategyContext.getTaskStatisticsRequirements()
     ).toStrictEqual({
-      runTime: false,
-      avgRunTime: false,
-      medRunTime: false,
-      waitTime: false,
-      avgWaitTime: false,
-      medWaitTime: false,
-      elu: false
+      runTime: {
+        aggregate: false,
+        average: false,
+        median: false
+      },
+      waitTime: {
+        aggregate: false,
+        average: false,
+        median: false
+      },
+      elu: {
+        aggregate: false,
+        average: false,
+        median: false
+      }
     })
     // We need to clean up the resources after our test
     await pool.destroy()
@@ -1189,18 +1827,32 @@ describe('Selection strategies test suite', () => {
           failed: 0
         },
         runTime: {
-          aggregation: 0,
+          aggregate: 0,
           average: 0,
           median: 0,
           history: expect.any(CircularArray)
         },
         waitTime: {
-          aggregation: 0,
+          aggregate: 0,
           average: 0,
           median: 0,
           history: expect.any(CircularArray)
         },
-        elu: undefined
+        elu: {
+          idle: {
+            aggregate: 0,
+            average: 0,
+            median: 0,
+            history: expect.any(CircularArray)
+          },
+          active: {
+            aggregate: 0,
+            average: 0,
+            median: 0,
+            history: expect.any(CircularArray)
+          },
+          utilization: 0
+        }
       })
     }
     expect(
@@ -1211,12 +1863,12 @@ describe('Selection strategies test suite', () => {
     expect(
       pool.workerChoiceStrategyContext.workerChoiceStrategies.get(
         pool.workerChoiceStrategyContext.workerChoiceStrategy
-      ).currentRoundId
+      ).roundId
     ).toBe(0)
     expect(
       pool.workerChoiceStrategyContext.workerChoiceStrategies.get(
         pool.workerChoiceStrategyContext.workerChoiceStrategy
-      ).currentWorkerNodeId
+      ).nextWorkerNodeId
     ).toBe(0)
     expect(
       pool.workerChoiceStrategyContext.workerChoiceStrategies.get(
@@ -1257,18 +1909,32 @@ describe('Selection strategies test suite', () => {
           failed: 0
         },
         runTime: {
-          aggregation: 0,
+          aggregate: 0,
           average: 0,
           median: 0,
           history: expect.any(CircularArray)
         },
         waitTime: {
-          aggregation: 0,
+          aggregate: 0,
           average: 0,
           median: 0,
           history: expect.any(CircularArray)
         },
-        elu: undefined
+        elu: {
+          idle: {
+            aggregate: 0,
+            average: 0,
+            median: 0,
+            history: expect.any(CircularArray)
+          },
+          active: {
+            aggregate: 0,
+            average: 0,
+            median: 0,
+            history: expect.any(CircularArray)
+          },
+          utilization: 0
+        }
       })
     }
     expect(
@@ -1279,12 +1945,12 @@ describe('Selection strategies test suite', () => {
     expect(
       pool.workerChoiceStrategyContext.workerChoiceStrategies.get(
         pool.workerChoiceStrategyContext.workerChoiceStrategy
-      ).currentRoundId
+      ).roundId
     ).toBe(0)
     expect(
       pool.workerChoiceStrategyContext.workerChoiceStrategies.get(
         pool.workerChoiceStrategyContext.workerChoiceStrategy
-      ).currentWorkerNodeId
+      ).nextWorkerNodeId
     ).toBe(0)
     expect(
       pool.workerChoiceStrategyContext.workerChoiceStrategies.get(
@@ -1309,12 +1975,12 @@ describe('Selection strategies test suite', () => {
     expect(
       pool.workerChoiceStrategyContext.workerChoiceStrategies.get(
         workerChoiceStrategy
-      ).currentRoundId
+      ).roundId
     ).toBeDefined()
     expect(
       pool.workerChoiceStrategyContext.workerChoiceStrategies.get(
         workerChoiceStrategy
-      ).currentWorkerNodeId
+      ).nextWorkerNodeId
     ).toBeDefined()
     expect(
       pool.workerChoiceStrategyContext.workerChoiceStrategies.get(
@@ -1330,12 +1996,12 @@ describe('Selection strategies test suite', () => {
     expect(
       pool.workerChoiceStrategyContext.workerChoiceStrategies.get(
         workerChoiceStrategy
-      ).currentRoundId
+      ).roundId
     ).toBe(0)
     expect(
       pool.workerChoiceStrategyContext.workerChoiceStrategies.get(
         pool.workerChoiceStrategyContext.workerChoiceStrategy
-      ).currentWorkerNodeId
+      ).nextWorkerNodeId
     ).toBe(0)
     expect(
       pool.workerChoiceStrategyContext.workerChoiceStrategies.get(
@@ -1360,12 +2026,12 @@ describe('Selection strategies test suite', () => {
     expect(
       pool.workerChoiceStrategyContext.workerChoiceStrategies.get(
         workerChoiceStrategy
-      ).currentRoundId
+      ).roundId
     ).toBeDefined()
     expect(
       pool.workerChoiceStrategyContext.workerChoiceStrategies.get(
         workerChoiceStrategy
-      ).currentWorkerNodeId
+      ).nextWorkerNodeId
     ).toBeDefined()
     expect(
       pool.workerChoiceStrategyContext.workerChoiceStrategies.get(
@@ -1381,7 +2047,7 @@ describe('Selection strategies test suite', () => {
     expect(
       pool.workerChoiceStrategyContext.workerChoiceStrategies.get(
         pool.workerChoiceStrategyContext.workerChoiceStrategy
-      ).currentWorkerNodeId
+      ).nextWorkerNodeId
     ).toBe(0)
     expect(
       pool.workerChoiceStrategyContext.workerChoiceStrategies.get(