Major API cleanup and porting to session-based interface

cs/benchmark/FasterYcsbBenchmark.cs

@@ -101,9 +101,9 @@ private void RunYcsb(int thread_idx)
             sw.Start();
 
 
-            Value value = default(Value);
-            Input input = default(Input);
-            Output output = default(Output);
+            Value value = default;
+            Input input = default;
+            Output output = default;
 
             long reads_done = 0;
             long writes_done = 0;
@@ -115,7 +115,7 @@ private void RunYcsb(int thread_idx)
             int count = 0;
 #endif
 
-            var session = store.StartClientSession(false);
+            var session = store.NewSession(null, false);
 
             while (!done)
             {
@@ -317,7 +317,7 @@ private void SetupYcsb(int thread_idx)
             else
                 Native32.AffinitizeThreadShardedNuma((uint)thread_idx, 2); // assuming two NUMA sockets
 
-            var session = store.StartClientSession(false);
+            var session = store.NewSession(null, false);
 
 #if DASHBOARD
             var tstart = Stopwatch.GetTimestamp();
@@ -326,7 +326,7 @@ private void SetupYcsb(int thread_idx)
             int count = 0;
 #endif
 
-            Value value = default(Value);
+            Value value = default;
 
             for (long chunk_idx = Interlocked.Add(ref idx_, kChunkSize) - kChunkSize;
                 chunk_idx < kInitCount;

cs/benchmark/Functions.cs

@@ -29,7 +29,7 @@ public void DeleteCompletionCallback(ref Key key, Empty ctx)
         {
         }
 
-        public void CheckpointCompletionCallback(Guid sessionId, CommitPoint commitPoint)
+        public void CheckpointCompletionCallback(string sessionId, CommitPoint commitPoint)
         {
             Debug.WriteLine("Session {0} reports persistence until {1}", sessionId, commitPoint.UntilSerialNo);
         }

cs/playground/ClassCache/Program.cs

@@ -18,7 +18,7 @@ class Program
         static readonly bool useReadCache = true;
         const int max = 1000000;
 
-        static void Main(string[] args)
+        static void Main()
         {
             // This sample shows the use of FASTER as a cache + key-value store for 
             // C# objects.
@@ -45,26 +45,22 @@ static void Main(string[] args)
                 );
 
             // Thread starts session with FASTER
-            h.StartSession();
+            var s = h.NewSession();
 
             Console.WriteLine("Writing keys from 0 to {0} to FASTER", max);
 
             Stopwatch sw = new Stopwatch();
             sw.Start();
             for (int i = 0; i < max; i++)
             {
-                if (i % 256 == 0)
+                if (i % (1<<19) == 0)
                 {
-                    h.Refresh();
-                    if (i % (1<<19) == 0)
-                    {
-                        long workingSet = Process.GetCurrentProcess().WorkingSet64;
-                        Console.WriteLine($"{i}: {workingSet / 1048576}M");
-                    }
+                    long workingSet = Process.GetCurrentProcess().WorkingSet64;
+                    Console.WriteLine($"{i}: {workingSet / 1048576}M");
                 }
                 var key = new CacheKey(i);
                 var value = new CacheValue(i);
-                h.Upsert(ref key, ref value, context, 0);
+                s.Upsert(ref key, ref value, context, 0);
             }
             sw.Stop();
             Console.WriteLine("Total time to upsert {0} elements: {1:0.000} secs ({2:0.00} inserts/sec)", max, sw.ElapsedMilliseconds/1000.0, max / (sw.ElapsedMilliseconds / 1000.0));
@@ -86,12 +82,12 @@ static void Main(string[] args)
             var workload = int.Parse(Console.ReadLine());
 
             if (workload == 0)
-                RandomReadWorkload(h, max);
+                RandomReadWorkload(s, max);
             else
-                InteractiveReadWorkload(h, max);
+                InteractiveReadWorkload(s);
 
             // Stop session and clean up
-            h.StopSession();
+            s.Dispose();
             h.Dispose();
             log.Close();
             objlog.Close();
@@ -100,7 +96,7 @@ static void Main(string[] args)
             Console.ReadLine();
         }
 
-        private static void RandomReadWorkload(FasterKV<CacheKey, CacheValue, CacheInput, CacheOutput, CacheContext, CacheFunctions> h, int max)
+        private static void RandomReadWorkload(ClientSession<CacheKey, CacheValue, CacheInput, CacheOutput, CacheContext, CacheFunctions> s, int max)
         {
             Console.WriteLine("Issuing uniform random read workload of {0} reads", max);
 
@@ -118,14 +114,14 @@ private static void RandomReadWorkload(FasterKV<CacheKey, CacheValue, CacheInput
                 long k = rnd.Next(max);
 
                 var key = new CacheKey(k);
-                var status = h.Read(ref key, ref input, ref output, context, 0);
+                var status = s.Read(ref key, ref input, ref output, context, 0);
 
                 switch (status)
                 {
                     case Status.PENDING:
                         statusPending++;
                         if (statusPending % 1000 == 0)
-                            h.CompletePending(false);
+                            s.CompletePending(false);
                         break;
                     case Status.OK:
                         if (output.value.value != key.key)
@@ -135,13 +131,13 @@ private static void RandomReadWorkload(FasterKV<CacheKey, CacheValue, CacheInput
                         throw new Exception("Error!");
                 }
             }
-            h.CompletePending(true);
+            s.CompletePending(true);
             sw.Stop();
             Console.WriteLine("Total time to read {0} elements: {1:0.000} secs ({2:0.00} reads/sec)", max, sw.ElapsedMilliseconds / 1000.0, max / (sw.ElapsedMilliseconds / 1000.0));
             Console.WriteLine($"Reads completed with PENDING: {statusPending}");
         }
 
-        private static void InteractiveReadWorkload(FasterKV<CacheKey, CacheValue, CacheInput, CacheOutput, CacheContext, CacheFunctions> h, int max)
+        private static void InteractiveReadWorkload(ClientSession<CacheKey, CacheValue, CacheInput, CacheOutput, CacheContext, CacheFunctions> s)
         {
             Console.WriteLine("Issuing interactive read workload");
 
@@ -158,11 +154,11 @@ private static void InteractiveReadWorkload(FasterKV<CacheKey, CacheValue, Cache
                 var key = new CacheKey(k);
 
                 context.ticks = DateTime.Now.Ticks;
-                var status = h.Read(ref key, ref input, ref output, context, 0);
+                var status = s.Read(ref key, ref input, ref output, context, 0);
                 switch (status)
                 {
                     case Status.PENDING:
-                        h.CompletePending(true);
+                        s.CompletePending(true);
                         break;
                     case Status.OK:
                         long ticks = DateTime.Now.Ticks - context.ticks;

cs/playground/ClassCache/Types.cs

@@ -113,7 +113,7 @@ public bool InPlaceUpdater(ref CacheKey key, ref CacheInput input, ref CacheValu
             throw new NotImplementedException();
         }
 
-        public void CheckpointCompletionCallback(Guid sessionId, CommitPoint commitPoint)
+        public void CheckpointCompletionCallback(string sessionId, CommitPoint commitPoint)
         {
             throw new NotImplementedException();
         }

cs/playground/ClassCacheMT/Program.cs

@@ -32,7 +32,7 @@ class Program
         static FasterKV<CacheKey, CacheValue, CacheInput, CacheOutput, CacheContext, CacheFunctions>[] h;
         static long totalReads = 0;
 
-        static void Main(string[] args)
+        static void Main()
         {
             // This sample shows the use of FASTER as a multi-threaded (MT) cache + key-value store for 
             // C# objects. Number of caches and number of threads can be varied.
@@ -62,31 +62,28 @@ static void Main(string[] args)
                     new SerializerSettings<CacheKey, CacheValue> { keySerializer = () => new CacheKeySerializer(), valueSerializer = () => new CacheValueSerializer() },
                     null
                     );
-                h[ht].StartSession();
+                var session = h[ht].NewSession();
                 Console.WriteLine("Table {0}:", ht);
                 Console.WriteLine("   Writing keys from 0 to {0} to FASTER", max);
 
                 Stopwatch sw = new Stopwatch();
                 sw.Start();
                 for (int i = 0; i < max; i++)
                 {
-                    if (i % 256 == 0)
+                    if (i % (1 << 19) == 0)
                     {
-                        h[ht].Refresh();
-                        if (i % (1 << 19) == 0)
-                        {
-                            // long workingSet = Process.GetCurrentProcess().WorkingSet64;
-                            // Console.WriteLine($"{i}: {workingSet / 1048576}M");
-                        }
+                        // long workingSet = Process.GetCurrentProcess().WorkingSet64;
+                        // Console.WriteLine($"{i}: {workingSet / 1048576}M");
                     }
+
                     var key = new CacheKey(i);
                     var value = new CacheValue(i);
-                    h[ht].Upsert(ref key, ref value, context, 0);
+                    session.Upsert(ref key, ref value, context, 0);
                 }
                 sw.Stop();
                 Console.WriteLine("   Total time to upsert {0} elements: {1:0.000} secs ({2:0.00} inserts/sec)", max, sw.ElapsedMilliseconds / 1000.0, max / (sw.ElapsedMilliseconds / 1000.0));
                 h[ht].Log.DisposeFromMemory();
-                h[ht].StopSession();
+                session.Dispose();
             }
 
             ContinuousRandomReadWorkload();
@@ -136,8 +133,11 @@ private static void RandomReadWorkload(int threadid)
         {
             Console.WriteLine("Issuing uniform random read workload of {0} reads from thread {1}", max, threadid);
 
+            ClientSession<CacheKey, CacheValue, CacheInput, CacheOutput, CacheContext, CacheFunctions>[]
+                sessions = new ClientSession<CacheKey, CacheValue, CacheInput, CacheOutput, CacheContext, CacheFunctions>[kNumTables];
+
             for (int ht = 0; ht < kNumTables; ht++)
-                h[ht].StartSession();
+                sessions[ht] = h[ht].NewSession();
 
             var rnd = new Random(threadid);
 
@@ -154,14 +154,14 @@ private static void RandomReadWorkload(int threadid)
                 if (i > 0 && (i % 256 == 0))
                 {
                     for (int htcnt = 0; htcnt < kNumTables; htcnt++)
-                        h[htcnt].CompletePending(false);
+                        sessions[htcnt].CompletePending(false);
                     Interlocked.Add(ref totalReads, 256);
                 }
                 long k = rnd.Next(max);
 
-                var ht = h[rnd.Next(kNumTables)];
+                var hts = sessions[rnd.Next(kNumTables)];
                 var key = new CacheKey(k);
-                var status = ht.Read(ref key, ref input, ref output, context, 0);
+                var status = hts.Read(ref key, ref input, ref output, context, 0);
 
                 switch (status)
                 {
@@ -183,7 +183,7 @@ private static void RandomReadWorkload(int threadid)
             Console.WriteLine($"Reads completed with PENDING: {statusPending}");
 
             for (int ht = 0; ht < kNumTables; ht++)
-                h[ht].StopSession();
+                sessions[ht].Dispose();
             */
         }
     }

cs/playground/ClassCacheMT/Types.cs

@@ -113,7 +113,7 @@ public bool InPlaceUpdater(ref CacheKey key, ref CacheInput input, ref CacheValu
             throw new NotImplementedException();
         }
 
-        public void CheckpointCompletionCallback(Guid sessionId, CommitPoint commitPoint)
+        public void CheckpointCompletionCallback(string sessionId, CommitPoint commitPoint)
         {
             throw new NotImplementedException();
         }

cs/playground/ClassSample/Program.cs

@@ -87,12 +87,12 @@ public void ReadCompletionCallback(ref MyKey key, ref MyInput input, ref MyOutpu
         public void UpsertCompletionCallback(ref MyKey key, ref MyValue value, MyContext ctx) { }
         public void RMWCompletionCallback(ref MyKey key, ref MyInput input, MyContext ctx, Status status) { }
         public void DeleteCompletionCallback(ref MyKey key, MyContext ctx) { }
-        public void CheckpointCompletionCallback(Guid sessionId, CommitPoint commitPoint) { }
+        public void CheckpointCompletionCallback(string sessionId, CommitPoint commitPoint) { }
     }
 
     class Program
     {
-        static void Main(string[] args)
+        static void Main()
         {
             // This sample uses class key and value types, which are not blittable (i.e., they
             // require a pointer to heap objects). Such datatypes include variable length types
@@ -116,21 +116,21 @@ static void Main(string[] args)
             var context = default(MyContext);
 
             // Each thread calls StartSession to register itself with FASTER
-            h.StartSession();
+            var s = h.NewSession();
 
             for (int i = 0; i < 20000; i++)
             {
                 var _key = new MyKey { key = i };
                 var value = new MyValue { value = i };
-                h.Upsert(ref _key, ref value, context, 0);
+                s.Upsert(ref _key, ref value, context, 0);
 
                 // Each thread calls Refresh periodically for thread coordination
-                if (i % 1024 == 0) h.Refresh();
+                if (i % 1024 == 0) s.Refresh();
             }
             var key = new MyKey { key = 23 };
             var input = default(MyInput);
             MyOutput g1 = new MyOutput();
-            var status = h.Read(ref key, ref input, ref g1, context, 0);
+            var status = s.Read(ref key, ref input, ref g1, context, 0);
 
             if (status == Status.OK && g1.value.value == key.key)
                 Console.WriteLine("Success!");
@@ -139,7 +139,7 @@ static void Main(string[] args)
 
             MyOutput g2 = new MyOutput();
             key = new MyKey { key = 46 };
-            status = h.Read(ref key, ref input, ref g2, context, 0);
+            status = s.Read(ref key, ref input, ref g2, context, 0);
 
             if (status == Status.OK && g2.value.value == key.key)
                 Console.WriteLine("Success!");
@@ -148,15 +148,15 @@ static void Main(string[] args)
 
             /// Delete key, read to verify deletion
             var output = new MyOutput();
-            h.Delete(ref key, context, 0);
-            status = h.Read(ref key, ref input, ref output, context, 0);
+            s.Delete(ref key, context, 0);
+            status = s.Read(ref key, ref input, ref output, context, 0);
             if (status == Status.NOTFOUND)
                 Console.WriteLine("Success!");
             else
                 Console.WriteLine("Error!");
 
             // Each thread ends session when done
-            h.StopSession();
+            s.Dispose();
 
             // Dispose FASTER instance and log
             h.Dispose();

cs/playground/FixedLenStructSample/Functions.cs

@@ -12,7 +12,7 @@ namespace FixedLenStructSample
     /// </summary>
     public class FixedLenFunctions : IFunctions<FixedLenKey, FixedLenValue, string, string, Empty>
     {
-        public void CheckpointCompletionCallback(Guid sessionId, CommitPoint commitPoint)
+        public void CheckpointCompletionCallback(string sessionId, CommitPoint commitPoint)
         {
         }
 

cs/playground/FixedLenStructSample/Program.cs

@@ -16,12 +16,13 @@ static void Main()
                 (128, new FixedLenFunctions(),
                 new LogSettings { LogDevice = log, MemorySizeBits = 17, PageSizeBits = 12 }
                 );
-            fht.StartSession();
+
+            var session = fht.NewSession();
 
             var key = new FixedLenKey("foo");
             var value = new FixedLenValue("bar");
 
-            var status = fht.Upsert(ref key, ref value, Empty.Default, 0);
+            var status = session.Upsert(ref key, ref value, Empty.Default, 0);
 
             if (status != Status.OK)
                 Console.WriteLine("FixedLenStructSample: Error!");
@@ -30,13 +31,13 @@ static void Main()
             var output = default(string);
 
             key = new FixedLenKey("xyz");
-            status = fht.Read(ref key, ref input, ref output, Empty.Default, 0);
+            status = session.Read(ref key, ref input, ref output, Empty.Default, 0);
 
             if (status != Status.NOTFOUND)
                 Console.WriteLine("FixedLenStructSample: Error!");
 
             key = new FixedLenKey("foo");
-            status = fht.Read(ref key, ref input, ref output, Empty.Default, 0);
+            status = session.Read(ref key, ref input, ref output, Empty.Default, 0);
 
             if (status != Status.OK)
                 Console.WriteLine("FixedLenStructSample: Error!");
@@ -46,7 +47,7 @@ static void Main()
             else
                 Console.WriteLine("FixedLenStructSample: Error!");
 
-            fht.StopSession();
+            session.Dispose();
             fht.Dispose();
             log.Close();
 

cs/playground/PeriodicCompaction/PeriodicCompaction.csproj

@@ -6,6 +6,7 @@
     <TargetFramework>net46</TargetFramework>
     <Platforms>x64</Platforms>
     <RuntimeIdentifier>win7-x64</RuntimeIdentifier>
+    <LangVersion>preview</LangVersion>
   </PropertyGroup>
 
   <ItemGroup>