public static void MultipleTasksFuzzyMatch()
{
var tasks = new List <Task <List <string> > >();
var matches = new List <string>();
BenchPerformance.Time("Multi Tasks Fuzzy Match",
iterations: Data.Iterations, operation: () =>
{
foreach (var word in WordsToSearch)
{
tasks.Add(Task.Factory.StartNew <List <string> >((w) =>
{
List <string> localMatches = new List <string>();
var localMathes = FuzzyMatch.JaroWinklerModule.bestMatch(Words, (string)w);
localMatches.AddRange(localMathes.Select(m => m.Word));
return(localMatches);
}, word));
}
Task.Factory.ContinueWhenAll(tasks.ToArray(), (ts) =>
{
matches = new List <string>(tasks.SelectMany(t => t.Result).Distinct());
}).Wait();
});
foreach (var match in matches)
{
Log(match);
}
Console.WriteLine();
}
// TODO
// (1) implement a fast fuzzy match
// you can use either PLINQ and/or Parallel loop. The latter requires attention to avoid race condition
#region Solution
public static void ParallelLoopFuzzyMatch()
{
List <string> matches = new List <string>();
BenchPerformance.Time("Parallel Loop Fuzzy Match",
iterations: Data.Iterations, operation: () =>
{
object sync = new object();
Parallel.ForEach(WordsToSearch,
// thread local initializer
() => { return(new List <string>()); },
(word, loopState, localMatches) =>
{
var localMathes = FuzzyMatch.JaroWinklerModule.bestMatch(Words, word);
localMatches.AddRange(localMathes.Select(m => m.Word)); // same code
return(localMatches);
},
(finalResult) =>
{
// thread local aggregator
lock (sync) matches.AddRange(finalResult);
}
);
});
foreach (var match in matches.Distinct())
{
Log(match);
}
}
public static void RunDemo(List <string> urls)
{
BenchPerformance.Time("Web crawler execution", () =>
{
var webPageTitles = from url in urls
from pageContent in WebCrawler(url)
select ExtractWebPageTitle(pageContent);
Console.WriteLine($"Crawled {webPageTitles.Count()} page titles");
});
BenchPerformance.Time("Web crawler execution using memoization", () =>
{
var webPageTitles = from url in urls
from pageContent in WebCrawlerMemoized(url)
select ExtractWebPageTitle(pageContent);
Console.WriteLine($"Crawled {webPageTitles.Count()} page titles");
});
BenchPerformance.Time("Thread-safe memoization function", () =>
{
var webPageTitles = from url in urls.AsParallel()
from pageContent in WebCrawlerMemoizedThreadSafe(url)
select ExtractWebPageTitle(pageContent);
Console.WriteLine($"Crawled {webPageTitles.Count()} page titles");
});
}
public static void Run(List <string> urls)
{
BenchPerformance.Time("Web crawler execution", () =>
{
var webPageTitles = from url in urls
from pageContent in WebCrawler(url)
select ExtractWebPageTitle(pageContent);
Console.WriteLine($"Crawled {webPageTitles.Count()} page titles");
});
BenchPerformance.Time("Web crawler execution using memoization", () =>
{
var webPageTitles = from url in urls
from pageContent in WebCrawlerMemoized(url)
select ExtractWebPageTitle(pageContent);
Console.WriteLine($"Crawled {webPageTitles.Count()} page titles");
});
BenchPerformance.Time("Thread-safe memoization function", () =>
{
// TODO : 1.2
// (1) implement parallel web crawler with thread safe memoization
// go to the Memoziation file
var webPageTitles = new int[] { };
Console.WriteLine($"Crawled {webPageTitles.Count()} page titles");
});
}
public static void ParallelLinqFuzzyMatch()
{
BenchPerformance.Time("Parallel Linq Fuzzy Match",
iterations: Data.Iterations, operation: () =>
{
ParallelQuery <string> matches = (from word in WordsToSearch.AsParallel()
from match in FuzzyMatch.JaroWinklerModule.bestMatch(Words, word)
select match.Word);
matches.ForAll(match =>
{
Log(match);
});
});
}
public static void LinqFuzzyMatch()
{
BenchPerformance.Time("Linq Fuzzy Match", () =>
{
var matches = (from word in WordsToSearch
from match in FuzzyMatch.JaroWinklerModule.bestMatch(Words, word)
select match.Word);
foreach (var match in matches)
{
Log(match);
}
});
}
static void Main(string[] args)
{
BenchPerformance.Time("Test", () =>
{
int sum = 0;
for (int i = 0; i < 100; i++)
{
sum += i;
}
}, 10);
Console.WriteLine("Hello World!");
Console.ReadLine();
}
public void ParallelArrayFuzzyMatch()
{
BenchPerformance.Time("Parallel Array F# Fuzzy Match", () =>
{
var matches = (from word in WordsToSearch
from match in FuzzyMatch.JaroWinklerModule.Parallel.bestMatch(Words, word)
select match.Word);
foreach (var match in matches)
{
Console.Write("{0}\t", match);
}
Console.WriteLine();
});
}
public static void ParallelLinqPartitionerFuzzyMatch()
{
BenchPerformance.Time("Parallel PLinq partitioner Fuzzy Match",
iterations: Data.Iterations, operation: () =>
{
var partitioner = Partitioner.Create(WordsToSearch, EnumerablePartitionerOptions.NoBuffering);
ParallelQuery <string> matches = (from word in WordsToSearch.AsParallel()
from match in FuzzyMatch.JaroWinklerModule.bestMatch(Words, word)
select match.Word);
matches.ForAll(match =>
{
Log(match);
});
});
}
public void ParallelLinqFuzzyMatch()
{
BenchPerformance.Time("Parallel Linq Fuzzy Match",
iterations: Data.Iterations, operation: () =>
{
ParallelQuery <string> matches = (from word in WordsToSearch.AsParallel()
from match in FuzzyMatch.JaroWinklerModule.bestMatch(Words, word)
select match.Word);
foreach (var match in matches)
{
Console.Write("{0}\t", match);
}
Console.WriteLine();
});
}
} // Console.Write("{0}\t", match);
public static void SequentialFuzzyMatch()
{
List <string> matches = new List <string>();
BenchPerformance.Time("Sequential Fuzzy Match", iterations: Data.Iterations, operation: () =>
{
foreach (var word in WordsToSearch)
{
var localMathes = FuzzyMatch.JaroWinklerModule.bestMatch(Words, word);
matches.AddRange(localMathes.Select(m => m.Word));
}
});
foreach (var match in matches.Distinct())
{
Log(match);
}
Console.WriteLine();
}
public void TwoThreadsFuzzyMatch()
{
List <string> matches = new List <string>();
BenchPerformance.Time("Two Thread Fuzzy Match",
iterations: Data.Iterations, operation: () =>
{
var t1 = new Thread(() =>
{
var take = WordsToSearch.Count / 2;
var start = 0;
foreach (var word in WordsToSearch.Take(take))
{
var localMathes = FuzzyMatch.JaroWinklerModule.bestMatch(Words, word);
matches.AddRange(localMathes.Select(m => m.Word));
}
});
var t2 = new Thread(() =>
{
var start = WordsToSearch.Count / 2;
var take = WordsToSearch.Count - start;
foreach (var word in WordsToSearch.Skip(start).Take(take))
{
var localMathes = FuzzyMatch.JaroWinklerModule.bestMatch(Words, word);
matches.AddRange(localMathes.Select(m => m.Word));
}
});
t1.Start();
t2.Start();
t1.Join();
t2.Join();
});
foreach (var match in matches.Distinct())
{
Console.Write("{0}\t", match);
}
Console.WriteLine();
}
public static void SumPrimeNumber_Reducer()
{
int len = 10000000;
Func <int, bool> isPrime = n =>
{
if (n == 1)
{
return(false);
}
if (n == 2)
{
return(true);
}
var boundary = (int)Math.Floor(Math.Sqrt(n));
for (int i = 2; i <= boundary; ++i)
{
if (n % i == 0)
{
return(false);
}
}
return(true);
};
// Parallel sum of a collection using parallel Reducer
BenchPerformance.Time("Parallel sum of a collection using parallel Reducer", () =>
{
// TODO
// calculate the total with parallel Reducer
//
// Note : if the "len" value increases over int.maxvalue, the LINQ/PLINQ "Sum" operator does not work.
// for example, the following code does not work. The reducer function should fix the issue
// var total = Enumerable.Range(0, len).Where(isPrime).AsParallel().Sum();
// implement the ReducePartitioner function
var total = ParallelReducer.ReducePartitioner(Enumerable.Range(0, len), i => i, (a, b) => a + b);
Console.WriteLine($"The total is {total}");
}, 5);
}
public void MultipleThreadsFuzzyMatch()
{
List <string> matches = new List <string>();
BenchPerformance.Time("Multi Thread Fuzzy Match",
iterations: Data.Iterations, operation: () =>
{
var threads = new Thread[Environment.ProcessorCount];
for (int i = 0; i < threads.Length; i++)
{
var index = i;
threads[index] = new Thread(() =>
{
var take = WordsToSearch.Count / (Math.Min(WordsToSearch.Count, threads.Length));
var start = index == threads.Length - 1 ? WordsToSearch.Count - take : index * take;
foreach (var word in WordsToSearch.Skip(start).Take(take))
{
var localMathes = FuzzyMatch.JaroWinklerModule.bestMatch(Words, word);
matches.AddRange(localMathes.Select(m => m.Word));
}
});
}
for (int i = 0; i < threads.Length; i++)
{
threads[i].Start();
}
for (int i = 0; i < threads.Length; i++)
{
threads[i].Join();
}
});
foreach (var match in matches.Distinct())
{
Console.Write("{0}\t", match);
}
Console.WriteLine();
}
public static void ThreadFuzzyMatch()
{
List <string> matches = new List <string>();
BenchPerformance.Time("Thread Fuzzy Match",
iterations: Data.Iterations, operation: () =>
{
var t = new Thread(() =>
{
foreach (var word in WordsToSearch)
{
var localMathes = FuzzyMatch.JaroWinklerModule.bestMatch(Words, word);
matches.AddRange(localMathes.Select(m => m.Word));
}
});
t.Start();
t.Join();
});
foreach (var match in matches.Distinct())
{
Log(match);
}
}
public static void FromZeroToPLINQ()
{
var numbers = Enumerable.Range(1, 1000000).ToArray();
var allocNums = Enumerable.Range(1, 10000000).ToArray();
BenchPerformance.Time("LINQ", () =>
{
var results = (from n in numbers
where SimpleAlghos.isPrime(n)
select n).ToArray();
}, 2);
BenchPerformance.Time("PLINQ", () =>
{
var results = (from n in numbers.AsParallel()
where SimpleAlghos.isPrime(n)
select n).ToArray();
}, 2);
BenchPerformance.Time("PLINQ REF TYPE", () =>
{
var results = (from n in allocNums.AsParallel()
select new { Value = n }).ToArray();
}, 2);
BenchPerformance.Time("PLINQ VALUE TYPE", () =>
{
var results = (from n in allocNums.AsParallel()
select new Wrapper {
Value = n
}).ToArray();
}, 2);
BenchPerformance.Time("SHARED SEQ", () =>
{
int[] count = new int[4];
for (int i = 0; i < 4; i++)
{
for (int j = 0; j < 100000000; j++)
{
count[i] = count[i] + j;
}
}
}, 2);
BenchPerformance.Time("SHARED PLINQ", () =>
{
int[] count = new int[4];
ParallelEnumerable.Range(0, 4).ForAll(i =>
{
for (int j = 0; j < 100000000; j++)
{
count[i] = count[i] + j;
}
});
}, 2);
BenchPerformance.Time("BETTER SHARED PLINQ", () =>
{
const int PADDING = 16;
int[] count = new int[5 * PADDING];
ParallelEnumerable.Range(0, 4).ForAll(i =>
{
int offset = (i + 1) * PADDING;
for (int j = 0; j < 100000000; j++)
{
count[offset] = count[offset] + j;
}
});
}, 2);
BenchPerformance.Time("ALTERNATIVE SHARED PLINQ", () =>
{
int[][] count = new int[4][];
ParallelEnumerable.Range(0, 4).ForAll(i =>
{
count[i] = new int[1];
for (int j = 0; j < 100000000; j++)
{
count[i][0] = count[i][0] + j;
}
});
}, 2);
}
static void ParallelFilterMap()
{
bool IsPrime(int n)
{
if (n == 1)
{
return(false);
}
if (n == 2)
{
return(true);
}
var boundary = (int)Math.Floor(Math.Sqrt(n));
for (int i = 2; i <= boundary; ++i)
{
if (n % i == 0)
{
return(false);
}
}
return(true);
}
BigInteger ToPow(int n) => (BigInteger)Math.BigMul(n, n);
var numbers = Enumerable.Range(0, 100000000).ToList();
BigInteger SeqOperation() => numbers.Where(IsPrime).Select(ToPow).Aggregate(BigInteger.Add);
BigInteger ParallelLinqOperation() => numbers.AsParallel().Where(IsPrime).Select(ToPow).Aggregate(BigInteger.Add);
// TODO : 6.6
// Update the FilterMap function to reduce the result into a single (or different) type.
// you should remove the ".Aggregate(BigInteger.Add)" part and add a reducer function.
// Keep parallelism and thread safety
BigInteger ParallelFilterMapInline() => numbers.FilterMap(IsPrime, ToPow).Aggregate(BigInteger.Add);
Console.WriteLine("Square Prime Sum [0..10000000]");
Func <Func <BigInteger>, Action> runSum = (func) =>
new Action(
() =>
{
var result = func();
Console.WriteLine($"Sum = {result}");
});
var sumImplementations =
new[]
{
new Tuple <String, Action>(
"C# Sequential", runSum(SeqOperation)),
new Tuple <String, Action>(
"C# Parallel LINQ", runSum(ParallelLinqOperation)),
new Tuple <String, Action>(
"C# Parallel FilterMap inline", runSum(ParallelFilterMapInline))
};
foreach (var item in sumImplementations)
{
BenchPerformance.Time(item.Item1, item.Item2);
}
}
public static void Run()
{
BenchPerformance.Time("Parallel Map Reduce word count", RunBookMapReduce, 5);
}
