examples/SFExamples/Example_RArray/ThrashingExamples.cpp

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Description:  
*/ 
#include "ThrashingExamples.h"
#include "SharedCode.h"
#include <e32test.h>

extern CConsoleBase* console;

// ---------------------------------------------------------
// TInt NaiveAddL()
// Adds to an array with a granularity of 1
// this is the worst possible performance
// ---------------------------------------------------------
//
LOCAL_C TInt NaiveAddL()
        {
        TExampleStruct* values = GenerateValuesLC();
        
        RExampleArray array(1);
    CleanupClosePushL(array);
    
    const TInt tickCountIn = User::TickCount();
    AddElementsL(values, array);
    User::After(0);
    const TInt tickCountOut = User::TickCount();
    
    CleanupStack::PopAndDestroy(2, values);
    
    return tickCountOut - tickCountIn;
        }

// ---------------------------------------------------------
// TInt GranulatedAddL()
// Adds to the array with a granularity of 5000
// Much better performance (~3x)
// ---------------------------------------------------------
//
LOCAL_C TInt GranulatedAddL()
        {
        TExampleStruct* values = GenerateValuesLC();
        
        RExampleArray array(KDefaultGranularity);
    CleanupClosePushL(array);
    
    const TInt tickCountIn = User::TickCount();
    AddElementsL(values, array);
    User::After(0);
    const TInt tickCountOut = User::TickCount();
    
    CleanupStack::PopAndDestroy(2, values);

    return (tickCountOut  - tickCountIn);
        }

// ---------------------------------------------------------
// void ThrashingExamplesL()
// Exmaples to illustrate thrashing
// ---------------------------------------------------------
//
void ThrashingExamplesL()
        {
        console->Printf(_L("Naive Add functions\n"));
        // This example shows the benefits of
        // using the granularity functionality
        // of RArray to reduce the memory thrashing
        // add or removing an array
    TInt avg = 0;
    TInt totalNaiveAddTimes = 0;
    for( TInt i=0; i < KTestRuns; i++)
        {
        totalNaiveAddTimes += NaiveAddL();
        }
    
    avg = (totalNaiveAddTimes / KTestRuns);
    console->Printf(_L("Average naive add (granularity 1, %d elements took %d Milliseconds\n"), KMaxElements, avg);

    console->Printf(_L("Granular Add functions"));
    TInt totalGranulatedAddTimes = 0;
    for( TInt i=0; i < KTestRuns; i++)
        {
        totalGranulatedAddTimes += GranulatedAddL();
        }
    
    avg = (totalGranulatedAddTimes / KTestRuns);
    console->Printf(_L("Average granulated add (granularity 5000, %d elements took %d Milliseconds\n"), KMaxElements, avg);
        }

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