Add the flushing denormal values option on BigDL side (#2934)

dding3 · Oct 28, 2019 · 94cf8ea · 94cf8ea
1 parent 2970c09
commit 94cf8ea
Show file tree

Hide file tree

Showing 2 changed files with 103 additions and 0 deletions.
diff --git a/scala/dllib/src/main/scala/com/intel/analytics/bigdl/dllib/utils/ThreadPool.scala b/scala/dllib/src/main/scala/com/intel/analytics/bigdl/dllib/utils/ThreadPool.scala
@@ -103,6 +103,10 @@ class ThreadPool(private var poolSize: Int) {
 
 
     this.invokeAndWait2((0 until 1).map(_ => () => {
+      if (System.getProperty("bigdl.flushDenormalState", "true").toBoolean) {
+        BackendMklDnn.setFlushDenormalState()
+      }
+
       require(MKL.isMKLLoaded)
       require(BackendMklDnn.isLoaded)
 

diff --git a/scala/dllib/src/test/scala/com/intel/analytics/bigdl/dllib/utils/ThreadPoolSpec.scala b/scala/dllib/src/test/scala/com/intel/analytics/bigdl/dllib/utils/ThreadPoolSpec.scala
@@ -17,6 +17,7 @@
 package com.intel.analytics.bigdl.utils
 
 import com.intel.analytics.bigdl.mkl.hardware.Affinity
+import com.intel.analytics.bigdl.tensor.Tensor
 import org.scalatest.{FlatSpec, Matchers}
 
 import scala.concurrent.ExecutionException
@@ -121,4 +122,102 @@ class ThreadPoolSpec extends FlatSpec with Matchers {
       results.foreach(_.get())
     }
   }
+
+  "setFlushDenormalState" should "influence float arithmetic operations" in {
+    val poolSize = 1
+    val ompSize = 4
+
+    val threadPool = new ThreadPool(poolSize)
+
+    System.setProperty("bigdl.flushDenormalState", "false")
+    threadPool.setMKLThreadOfMklDnnBackend(ompSize)
+
+    threadPool.invokeAndWait2( (0 until 1).map(i => () => {
+      // A denormalized value is in the range
+      // from 1.4E-45 to 1.18E-38,
+      // or from -1.18E-38 to -1.4E-45
+      val denormal: Float = -1.234E-41F
+      val floatOne: Float = 1.0F
+
+      val result: Float = denormal * floatOne
+      // The result should not be zero without setting
+      (result == 0.0F) should be(false)
+    }))
+
+    System.setProperty("bigdl.flushDenormalState", "true")
+    threadPool.setMKLThreadOfMklDnnBackend(ompSize)
+
+    threadPool.invokeAndWait2( (0 until 1).map(i => () => {
+      // A denormalized value is in the range
+      // from 1.4E-45 to 1.18E-38,
+      // or from -1.18E-38 to -1.4E-45
+      val denormal: Float = -1.234E-41F
+      val floatOne: Float = 1.0F
+
+      val result = denormal * floatOne
+      // The result should be zero with setting
+      (result == 0.0F) should be (true)
+    }))
+
+    System.clearProperty("bigdl.flushDenormalState")
+  }
+
+  "setFlushDenormalState" should "not influence other threads float arithmetic operations" in {
+    val poolSize = 1
+    val ompSize = 4
+
+    val threadPool1 = new ThreadPool(poolSize)
+    System.setProperty("bigdl.flushDenormalState", "true")
+    threadPool1.setMKLThreadOfMklDnnBackend(ompSize)
+
+    val threadPool2 = new ThreadPool(poolSize)
+    System.setProperty("bigdl.flushDenormalState", "false")
+    threadPool2.setMKLThreadOfMklDnnBackend(ompSize)
+
+    // A denormalized value is in the range
+    // from 1.4E-45 to 1.18E-38,
+    // or from -1.18E-38 to -1.4E-45
+    val denormal: Float = -1.234E-41F
+    val floatOne: Float = 1.0F
+
+    threadPool1.invokeAndWait2( (0 until 1).map(i => () => {
+      val result = denormal * floatOne
+      // The result should be zero with setting
+      (result == 0.0F) should be (true)
+    }))
+
+    threadPool2.invokeAndWait2( (0 until 1).map(i => () => {
+      val result = denormal * floatOne
+      // The result should not be zero without setting
+      (result == 0.0F) should be (false)
+    }))
+
+    System.clearProperty("bigdl.flushDenormalState")
+  }
+
+  "setFlushDenormalState" should "not influence other threads MKL operations" in {
+    val poolSize = 1
+    val ompSize = 4
+
+    val threadPool1 = new ThreadPool(poolSize)
+    System.setProperty("bigdl.flushDenormalState", "false")
+    threadPool1.setMKLThreadOfMklDnnBackend(ompSize)
+
+    val threadPool2 = new ThreadPool(poolSize)
+    System.setProperty("bigdl.flushDenormalState", "true")
+    threadPool2.setMKLThreadOfMklDnnBackend(ompSize)
+
+    val tensor = Tensor[Float](1).fill(-1.234E-41F)
+    val floatOne = 1.0F
+
+    threadPool1.invokeAndWait2( (0 until 1).map(i => () => {
+      val result = tensor.pow(floatOne)
+
+      for (i <- 0 to result.storage().array().length -1) {
+        assert(result.storage().array()(i) != 0.0F)
+      }
+    }))
+
+    System.clearProperty("bigdl.flushDenormalState")
+  }
 }