HPCC-29838 Add false sharing test case

Signed-off-by: Richard Chapman <[email protected]>
hpcc-systems · Jul 26, 2023 · 2e40cea · 2e40cea
1 parent 9e395ea
commit 2e40cea
Showing 1 changed file with 125 additions and 0 deletions.
diff --git a/testing/unittests/unittests.cpp b/testing/unittests/unittests.cpp
@@ -928,4 +928,129 @@ CPPUNIT_TEST_SUITE_REGISTRATION( PipeRunTest );
 CPPUNIT_TEST_SUITE_NAMED_REGISTRATION( PipeRunTest, "PipeRunTest" );
 #endif
 
+class RelaxedAtomicTimingTest : public CppUnit::TestFixture
+{
+    CPPUNIT_TEST_SUITE( RelaxedAtomicTimingTest  );
+        CPPUNIT_TEST(testRun);
+    CPPUNIT_TEST_SUITE_END();
+
+    void testRun()
+    {
+        testRunner(0);
+        testRunner(1);
+        testRunner(2);
+        testRunner(3);
+        testRunner(4);
+    }
+
+    void testRunner(unsigned mode)
+    {
+        CCycleTimer timer;
+        unsigned count = 100000000;
+        RelaxedAtomic<int> ra[201];
+        CriticalSection lock[201];
+
+        for (int a = 0; a < 201; a++)
+            ra[a] = 0;
+
+        class T : public CThreaded
+        {
+        public:
+            T(unsigned _count, RelaxedAtomic<int> &_ra, CriticalSection &_lock, unsigned _mode) : CThreaded(""), count(_count), ra(_ra), lock(_lock), mode(_mode) 
+            {}
+            virtual int run() override
+            {
+                switch(mode)
+                {
+                    case 0: test0(); break;
+                    case 1: test1(); break;
+                    // Disabled next two for now as slow and not especially interesting
+                    // case 2: test2(); break;
+                    // case 3: test3(); break;
+                    case 4: test4(); break;
+                }
+                return 0;
+            }
+            void test0()
+            {
+                RelaxedAtomic<int> &a = ra;
+                while (count--)
+                    a++;
+            }
+            void test1()
+            {
+                RelaxedAtomic<int> &a = ra;
+                while (count--)
+                    a.fastAdd(1);
+            }
+            void test2()
+            {
+                int &a = (int &) ra;
+                while (count--)
+                {
+                    CriticalBlock b(lock);
+                    a++;
+                }
+            }
+            void test3()
+            {
+                RelaxedAtomic<int> &a = ra;
+                while (count--)
+                {
+                    CriticalBlock b(lock);
+                    a.fastAdd(1);
+                }
+            }
+            void test4()
+            {
+                int &a = (int &) ra;
+                while (count--)
+                {
+                    if (a != count)
+                        a++;
+                }
+                ra = a;
+            }
+
+            unsigned mode;
+            unsigned count;
+            RelaxedAtomic<int> &ra;
+            CriticalSection &lock;
+        } t1a(count, ra[0], lock[0], mode), t2a(count, ra[0], lock[0], mode), t3a(count, ra[0], lock[0], mode),
+          t1b(count, ra[0], lock[0], mode), t2b(count, ra[1], lock[1], mode), t3b(count, ra[2], lock[2], mode),
+          t1c(count, ra[0], lock[0], mode), t2c(count, ra[100], lock[100], mode), t3c(count, ra[200], lock[200], mode);;  
+        DBGLOG("Testing RelaxedAtomics (test mode %u)", mode);
+        t1a.start();
+        t2a.start();
+        t3a.start();
+        t1a.join();
+        t2a.join();
+        t3a.join();
+        DBGLOG("Same RAs took %ums, value %d", timer.elapsedMs(), ra[0]+0);
+        for (int a = 0; a < 201; a++)
+            ra[a] = 0;
+        timer.reset();
+        t1b.start();
+        t2b.start();
+        t3b.start();
+        t1b.join();
+        t2b.join();
+        t3b.join();
+        DBGLOG("Adjacent RAs took %ums, values %d %d %d", timer.elapsedMs(), ra[0]+0, ra[1]+0, ra[2]+0);
+        for (int a = 0; a < 201; a++)
+            ra[a] = 0;
+        timer.reset();
+        t1c.start();
+        t2c.start();
+        t3c.start();
+        t1c.join();
+        t2c.join();
+        t3c.join();
+        DBGLOG("Spaced RAs took %ums, values %d %d %d", timer.elapsedMs(), ra[0]+0, ra[100]+0, ra[200]+0);
+    }
+};
+
+CPPUNIT_TEST_SUITE_REGISTRATION( RelaxedAtomicTimingTest );
+CPPUNIT_TEST_SUITE_NAMED_REGISTRATION( RelaxedAtomicTimingTest, "RelaxedAtomicTimingTest" );
+
 #endif // _USE_CPPUNIT