Change NodeStore::Backend tests to reflect observed patterns:

Empirical evidence shows a database access pattern with few hits
and many misses (objects that don't exist). This changes the timing
tests so they more accurately reflect rippled's actual usage:
* Add read missing keys test
* Increase numObjectsToTest to 1,000,000
* Alter PredictableObjectFactory to seed RNG once only
* Make NodeStoreTiming a manual test

src/ripple/nodestore/tests/BackendTests.cpp

@@ -43,7 +43,7 @@ public:
 
         // Create a batch
         Batch batch;
-        createPredictableBatch (batch, 0, numObjectsToTest, seedValue);
+        createPredictableBatch (batch, numObjectsToTest, seedValue);
 
         beast::Journal j;
 

src/ripple/nodestore/tests/BasicTests.cpp

@@ -31,15 +31,15 @@ public:
         testcase ("batch");
 
         Batch batch1;
-        createPredictableBatch (batch1, 0, numObjectsToTest, seedValue);
+        createPredictableBatch (batch1, numObjectsToTest, seedValue);
 
         Batch batch2;
-        createPredictableBatch (batch2, 0, numObjectsToTest, seedValue);
+        createPredictableBatch (batch2, numObjectsToTest, seedValue);
 
         expect (areBatchesEqual (batch1, batch2), "Should be equal");
 
         Batch batch3;
-        createPredictableBatch (batch3, 1, numObjectsToTest, seedValue);
+        createPredictableBatch (batch3, numObjectsToTest, seedValue+1);
 
         expect (! areBatchesEqual (batch1, batch3), "Should not be equal");
     }
@@ -50,7 +50,7 @@ public:
         testcase ("encoding");
 
         Batch batch;
-        createPredictableBatch (batch, 0, numObjectsToTest, seedValue);
+        createPredictableBatch (batch, numObjectsToTest, seedValue);
 
         EncodedBlob encoded;
         for (int i = 0; i < batch.size (); ++i)

src/ripple/nodestore/tests/DatabaseTests.cpp

@@ -37,7 +37,7 @@ public:
 
         // Create a batch
         Batch batch;
-        createPredictableBatch (batch, 0, numObjectsToTest, seedValue);
+        createPredictableBatch (batch, numObjectsToTest, seedValue);
 
         beast::Journal j;
 
@@ -113,7 +113,7 @@ public:
 
         // Create a batch
         Batch batch;
-        createPredictableBatch (batch, 0, numObjectsToTest, seedValue);
+        createPredictableBatch (batch, numObjectsToTest, seedValue);
 
         beast::Journal j;
 

src/ripple/nodestore/tests/TestBase.h

@@ -44,14 +44,12 @@ public:
     {
     public:
         explicit PredictableObjectFactory (std::int64_t seedValue)
-            : m_seedValue (seedValue)
+            : r (seedValue)
         {
         }
 
-        NodeObject::Ptr createObject (int index)
+        NodeObject::Ptr createObject ()
         {
-            beast::Random r (m_seedValue + index);
-
             NodeObjectType type;
             switch (r.nextInt (4))
             {
@@ -79,20 +77,19 @@ public:
         }
 
     private:
-        std::int64_t const m_seedValue;
+        beast::Random r;
     };
 
 public:
-    // Create a predictable batch of objects
-    static void createPredictableBatch (Batch& batch, int startingIndex,
-                                        int numObjects, std::int64_t seedValue)
-    {
+ // Create a predictable batch of objects
+ static void createPredictableBatch(Batch& batch, int numObjects,
+                                    std::int64_t seedValue) {
         batch.reserve (numObjects);
 
         PredictableObjectFactory factory (seedValue);
 
         for (int i = 0; i < numObjects; ++i)
-            batch.push_back (factory.createObject (startingIndex + i));
+            batch.push_back (factory.createObject ());
     }
 
     // Compare two batches for equality
@@ -152,6 +149,19 @@ public:
         }
     }
 
+    void fetchMissing(Backend& backend, Batch const& batch)
+    {
+        for (int i = 0; i < batch.size (); ++i)
+        {
+            NodeObject::Ptr object;
+
+            Status const status = backend.fetch (
+                batch [i]->getHash ().cbegin (), &object);
+
+            expect (status == notFound, "Should be notFound");
+        }
+    }
+
     // Store all objects in a batch
     static void storeBatch (Database& db, Batch const& batch)
     {

src/ripple/nodestore/tests/TimingTests.cpp

@@ -25,7 +25,7 @@ class NodeStoreTiming_test : public TestBase
 public:
     enum
     {
-        numObjectsToTest     = 10000
+        numObjectsToTest     = 1000000
     };
 
     class Stopwatch
@@ -68,9 +68,11 @@ public:
 
         // Create batches
         NodeStore::Batch batch1;
-        createPredictableBatch (batch1, 0, numObjectsToTest, seedValue);
+        createPredictableBatch (batch1, numObjectsToTest, seedValue);
         NodeStore::Batch batch2;
-        createPredictableBatch (batch2, 0, numObjectsToTest, seedValue);
+        createPredictableBatch (batch2, numObjectsToTest, seedValue);
+        NodeStore::Batch missingBatch;
+        createPredictableBatch (missingBatch, numObjectsToTest, seedValue+1);
 
         beast::Journal j;
 
@@ -83,19 +85,24 @@ public:
         // Individual write batch test
         t.start ();
         storeBatch (*backend, batch1);
-        log << "  Single write: " << std::to_string (t.getElapsed ()) << " seconds";
+        log << "  Single write:       " << std::to_string (t.getElapsed ()) << " seconds";
 
         // Bulk write batch test
         t.start ();
         backend->storeBatch (batch2);
-        log << "  Batch write:  " << std::to_string (t.getElapsed ()) << " seconds";
+        log << "  Batch write:        " << std::to_string (t.getElapsed ()) << " seconds";
 
         // Read test
         Batch copy;
         t.start ();
         fetchCopyOfBatch (*backend, &copy, batch1);
         fetchCopyOfBatch (*backend, &copy, batch2);
-        log << "  Batch read:   " << std::to_string (t.getElapsed ()) << " seconds";
+        log << "  Batch read:         " << std::to_string (t.getElapsed ()) << " seconds";
+
+        // Read missing keys test
+        t.start ();
+        fetchMissing (*backend, missingBatch);
+        log << "  Batch read missing: " << std::to_string (t.getElapsed ()) << " seconds";
     }
 
     //--------------------------------------------------------------------------
@@ -120,7 +127,7 @@ public:
     }
 };
 
-BEAST_DEFINE_TESTSUITE(NodeStoreTiming,ripple_core,ripple);
+BEAST_DEFINE_TESTSUITE_MANUAL(NodeStoreTiming,ripple_core,ripple);
 
 }
 }