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authorLiang Qi <liang.qi@theqtcompany.com>2016-01-26 14:35:50 +0100
committerLiang Qi <liang.qi@theqtcompany.com>2016-01-26 16:27:28 +0100
commita15c3d086dafea83e4760f0b447be43d26b80697 (patch)
treefd224a3f83942ff4c432e1e3a3f8583d14d6a11c /src/concurrent
parent87abfd351af6309691d921ca0aef077d74df4732 (diff)
parent397061a6a92db9f962360d5db96f69b315f93074 (diff)
Merge remote-tracking branch 'origin/5.6' into dev
Conflicts: src/android/jar/src/org/qtproject/qt5/android/QtActivityDelegate.java src/dbus/qdbusconnection_p.h src/dbus/qdbusintegrator.cpp src/dbus/qdbusintegrator_p.h tests/auto/corelib/io/qdir/qdir.pro tests/auto/corelib/io/qiodevice/tst_qiodevice.cpp Change-Id: I3d3fd07aed015c74b1f545f1327aa73d5f365fcc
Diffstat (limited to 'src/concurrent')
-rw-r--r--src/concurrent/qtconcurrentiteratekernel.cpp52
-rw-r--r--src/concurrent/qtconcurrentiteratekernel.h28
-rw-r--r--src/concurrent/qtconcurrentmedian.h66
3 files changed, 145 insertions, 1 deletions
diff --git a/src/concurrent/qtconcurrentiteratekernel.cpp b/src/concurrent/qtconcurrentiteratekernel.cpp
index b3f290998c..a04f0d66cc 100644
--- a/src/concurrent/qtconcurrentiteratekernel.cpp
+++ b/src/concurrent/qtconcurrentiteratekernel.cpp
@@ -188,6 +188,58 @@ int BlockSizeManager::blockSize()
return m_blockSize;
}
+/*! \internal
+
+*/
+BlockSizeManagerV2::BlockSizeManagerV2(int iterationCount)
+ : maxBlockSize(iterationCount / (QThreadPool::globalInstance()->maxThreadCount() * 2)),
+ beforeUser(0), afterUser(0),
+ m_blockSize(1)
+{ }
+
+// Records the time before user code.
+void BlockSizeManagerV2::timeBeforeUser()
+{
+ if (blockSizeMaxed())
+ return;
+
+ beforeUser = getticks();
+ controlPartElapsed.addValue(elapsed(beforeUser, afterUser));
+}
+
+ // Records the time after user code and adjust the block size if we are spending
+ // to much time in the for control code compared with the user code.
+void BlockSizeManagerV2::timeAfterUser()
+{
+ if (blockSizeMaxed())
+ return;
+
+ afterUser = getticks();
+ userPartElapsed.addValue(elapsed(afterUser, beforeUser));
+
+ if (controlPartElapsed.isMedianValid() == false)
+ return;
+
+ if (controlPartElapsed.median() * TargetRatio < userPartElapsed.median())
+ return;
+
+ m_blockSize = qMin(m_blockSize * 2, maxBlockSize);
+
+#ifdef QTCONCURRENT_FOR_DEBUG
+ qDebug() << QThread::currentThread() << "adjusting block size" << controlPartElapsed.median() << userPartElapsed.median() << m_blockSize;
+#endif
+
+ // Reset the medians after adjusting the block size so we get
+ // new measurements with the new block size.
+ controlPartElapsed.reset();
+ userPartElapsed.reset();
+}
+
+int BlockSizeManagerV2::blockSize()
+{
+ return m_blockSize;
+}
+
} // namespace QtConcurrent
QT_END_NAMESPACE
diff --git a/src/concurrent/qtconcurrentiteratekernel.h b/src/concurrent/qtconcurrentiteratekernel.h
index 2540f2f9be..b4360abd26 100644
--- a/src/concurrent/qtconcurrentiteratekernel.h
+++ b/src/concurrent/qtconcurrentiteratekernel.h
@@ -88,6 +88,32 @@ private:
Q_DISABLE_COPY(BlockSizeManager)
};
+// ### Qt6: Replace BlockSizeManager with V2 implementation
+class Q_CONCURRENT_EXPORT BlockSizeManagerV2
+{
+public:
+ explicit BlockSizeManagerV2(int iterationCount);
+
+ void timeBeforeUser();
+ void timeAfterUser();
+ int blockSize();
+
+private:
+ inline bool blockSizeMaxed()
+ {
+ return (m_blockSize >= maxBlockSize);
+ }
+
+ const int maxBlockSize;
+ qint64 beforeUser;
+ qint64 afterUser;
+ MedianDouble controlPartElapsed;
+ MedianDouble userPartElapsed;
+ int m_blockSize;
+
+ Q_DISABLE_COPY(BlockSizeManagerV2)
+};
+
template <typename T>
class ResultReporter
{
@@ -196,7 +222,7 @@ public:
ThreadFunctionResult forThreadFunction()
{
- BlockSizeManager blockSizeManager(iterationCount);
+ BlockSizeManagerV2 blockSizeManager(iterationCount);
ResultReporter<T> resultReporter(this);
for(;;) {
diff --git a/src/concurrent/qtconcurrentmedian.h b/src/concurrent/qtconcurrentmedian.h
index 78c2719838..d0f832812c 100644
--- a/src/concurrent/qtconcurrentmedian.h
+++ b/src/concurrent/qtconcurrentmedian.h
@@ -127,6 +127,72 @@ private:
bool dirty;
};
+// ### Qt6: Drop Median<double> in favor of this faster MedianDouble
+class MedianDouble
+{
+public:
+ enum { BufferSize = 7 };
+
+ MedianDouble()
+ : currentMedian(), currentIndex(0), valid(false), dirty(true)
+ {
+ }
+
+ void reset()
+ {
+ std::fill_n(values, static_cast<int>(BufferSize), 0.0);
+ currentIndex = 0;
+ valid = false;
+ dirty = true;
+ }
+
+ void addValue(double value)
+ {
+ ++currentIndex;
+ if (currentIndex == BufferSize) {
+ currentIndex = 0;
+ valid = true;
+ }
+
+ // Only update the cached median value when we have to, that
+ // is when the new value is on then other side of the median
+ // compared to the current value at the index.
+ const double currentIndexValue = values[currentIndex];
+ if ((currentIndexValue > currentMedian && currentMedian > value)
+ || (currentMedian > currentIndexValue && value > currentMedian)) {
+ dirty = true;
+ }
+
+ values[currentIndex] = value;
+ }
+
+ bool isMedianValid() const
+ {
+ return valid;
+ }
+
+ double median()
+ {
+ if (dirty) {
+ dirty = false;
+
+ double sorted[BufferSize];
+ ::memcpy(&sorted, &values, sizeof(sorted));
+ std::sort(sorted, sorted + static_cast<int>(BufferSize));
+ currentMedian = sorted[BufferSize / 2];
+ }
+
+ return currentMedian;
+ }
+
+private:
+ double values[BufferSize];
+ double currentMedian;
+ int currentIndex;
+ bool valid;
+ bool dirty;
+};
+
} // namespace QtConcurrent
#endif //Q_QDOC