repositories / poolifier.git / blobdiff
? search:
summary | shortlog | log | commit | commitdiff | tree
raw | inline | side by side
test: improve worker choice strategies options coverage
[poolifier.git] / tests / pools / selection-strategies / selection-strategies.test.js
diff --git a/tests/pools/selection-strategies/selection-strategies.test.js b/tests/pools/selection-strategies/selection-strategies.test.js
index f81ae9039da2cce52671f094b77cfb248173b530..6091bf080f327a3218f53522fcfd1780ef543a70 100644 (file)
--- a/tests/pools/selection-strategies/selection-strategies.test.js
+++ b/tests/pools/selection-strategies/selection-strategies.test.js
@@ -14,8 +14,8 @@ describe('Selection strategies test suite', () => {
   it('Verify that WorkerChoiceStrategies enumeration provides string values', () => {
     expect(WorkerChoiceStrategies.ROUND_ROBIN).toBe('ROUND_ROBIN')
     expect(WorkerChoiceStrategies.LEAST_USED).toBe('LEAST_USED')
-    expect(WorkerChoiceStrategies.LEAST_ELU).toBe('LEAST_ELU')
     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'
@@ -98,7 +98,7 @@ describe('Selection strategies test suite', () => {
         expect(
           pool.workerChoiceStrategyContext.workerChoiceStrategies.get(
             workerChoiceStrategy
-          ).currentWorkerNodeId
+          ).nextWorkerNodeId
         ).toBe(0)
         expect(
           pool.workerChoiceStrategyContext.workerChoiceStrategies.get(
@@ -115,7 +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,
@@ -125,13 +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(
@@ -143,13 +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()
@@ -177,18 +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(
@@ -223,18 +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(
@@ -312,7 +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,
@@ -322,13 +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(
@@ -340,13 +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()
@@ -368,25 +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()
@@ -409,32 +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,
@@ -444,13 +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(
@@ -462,13 +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()
@@ -496,24 +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
       )
     }
@@ -544,30 +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,
@@ -577,13 +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(
@@ -595,13 +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()
@@ -623,27 +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(
@@ -671,27 +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(
@@ -710,7 +1206,7 @@ describe('Selection strategies test suite', () => {
       {
         workerChoiceStrategy: WorkerChoiceStrategies.FAIR_SHARE,
         workerChoiceStrategyOptions: {
-          medRunTime: true
+          runTime: { median: true }
         }
       }
     )
@@ -724,27 +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(
@@ -829,7 +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,
@@ -839,13 +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(
@@ -857,13 +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()
@@ -891,26 +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(
@@ -950,24 +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(
@@ -992,7 +1574,7 @@ describe('Selection strategies test suite', () => {
       {
         workerChoiceStrategy: WorkerChoiceStrategies.WEIGHTED_ROUND_ROBIN,
         workerChoiceStrategyOptions: {
-          medRunTime: true
+          runTime: { median: true }
         }
       }
     )
@@ -1012,24 +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(
@@ -1055,7 +1651,7 @@ describe('Selection strategies test suite', () => {
     expect(
       pool.workerChoiceStrategyContext.workerChoiceStrategies.get(
         workerChoiceStrategy
-      ).currentWorkerNodeId
+      ).nextWorkerNodeId
     ).toBeDefined()
     expect(
       pool.workerChoiceStrategyContext.workerChoiceStrategies.get(
@@ -1071,7 +1667,7 @@ describe('Selection strategies test suite', () => {
     expect(
       pool.workerChoiceStrategyContext.workerChoiceStrategies.get(
         pool.workerChoiceStrategyContext.workerChoiceStrategy
-      ).currentWorkerNodeId
+      ).nextWorkerNodeId
     ).toBe(0)
     expect(
       pool.workerChoiceStrategyContext.workerChoiceStrategies.get(
@@ -1092,7 +1688,7 @@ describe('Selection strategies test suite', () => {
     expect(
       pool.workerChoiceStrategyContext.workerChoiceStrategies.get(
         workerChoiceStrategy
-      ).currentWorkerNodeId
+      ).nextWorkerNodeId
     ).toBeDefined()
     expect(
       pool.workerChoiceStrategyContext.workerChoiceStrategies.get(
@@ -1108,7 +1704,7 @@ describe('Selection strategies test suite', () => {
     expect(
       pool.workerChoiceStrategyContext.workerChoiceStrategies.get(
         pool.workerChoiceStrategyContext.workerChoiceStrategy
-      ).currentWorkerNodeId
+      ).nextWorkerNodeId
     ).toBe(0)
     expect(
       pool.workerChoiceStrategyContext.workerChoiceStrategies.get(
@@ -1124,7 +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(
@@ -1135,13 +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(
@@ -1153,13 +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()
@@ -1190,18 +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(
@@ -1212,12 +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(
@@ -1258,18 +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(
@@ -1280,12 +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(
@@ -1310,12 +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(
@@ -1331,12 +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(
@@ -1361,12 +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(
@@ -1382,7 +2047,7 @@ describe('Selection strategies test suite', () => {
     expect(
       pool.workerChoiceStrategyContext.workerChoiceStrategies.get(
         pool.workerChoiceStrategyContext.workerChoiceStrategy
-      ).currentWorkerNodeId
+      ).nextWorkerNodeId
     ).toBe(0)
     expect(
       pool.workerChoiceStrategyContext.workerChoiceStrategies.get(
Fast and small Node.js thread pool implementation mirror - https://github.com/poolifier/poolifier