Merge pull request #19 from ledjon-behluli/stream-loading-space

Startup loading behavior batch vs al

src/OrleanSpaces/Agents/BaseAgent.cs

@@ -41,16 +41,11 @@ public BaseAgent(
 
     async ValueTask ISpaceRouter<TTuple, TTemplate>.RouteDirector(IStoreDirector<TTuple> director)
     {
+        this.director = director;
         if (options.LoadSpaceContentsUponStartup)
         {
-            var tuples = await director.GetAll();
-            foreach (var tuple in tuples)
-            {
-                this.tuples.Add(tuple);
-            }
+            await ReloadAsync();
         }
-
-        this.director = director;
     }
 
     async ValueTask ISpaceRouter<TTuple, TTemplate>.RouteAction(TupleAction<TTuple> action)
@@ -194,7 +189,21 @@ public async IAsyncEnumerable<TTuple> EnumerateAsync(TTemplate template)
         }
     }
 
-    public async Task ReloadAsync() => tuples = await director.GetAll();
+    public async Task ReloadAsync()
+    {
+        if (options.LoadingStrategy == SpaceLoadingStrategy.Sequential)
+        {
+            tuples = tuples.Clear();
+            await foreach (var items in director.GetBatch())
+            {
+                tuples = tuples.AddRange(items);
+            }
+        }
+        else
+        {
+            tuples = await director.GetAllBatches();
+        }
+    }
 
     public async Task ClearAsync()
     {

src/OrleanSpaces/Agents/SpaceAgent.cs

@@ -37,12 +37,11 @@ public SpaceAgent(
 
     async ValueTask ISpaceRouter<SpaceTuple, SpaceTemplate>.RouteDirector(IStoreDirector<SpaceTuple> director)
     {
+        this.director = director;
         if (options.LoadSpaceContentsUponStartup)
         {
-            tuples = await director.GetAll();
+            await ReloadAsync();
         }
-
-        this.director = director;
     }
 
     async ValueTask ISpaceRouter<SpaceTuple, SpaceTemplate>.RouteAction(TupleAction<SpaceTuple> action)
@@ -187,7 +186,21 @@ public async IAsyncEnumerable<SpaceTuple> EnumerateAsync(SpaceTemplate template)
         }
     }
 
-    public async Task ReloadAsync() => tuples = await director.GetAll();
+    public async Task ReloadAsync()
+    {
+        if (options.LoadingStrategy == SpaceLoadingStrategy.Sequential)
+        {
+            tuples = tuples.Clear();
+            await foreach (var items in director.GetBatch())
+            {
+                tuples = tuples.AddRange(items);
+            }
+        }
+        else
+        {
+            tuples = await director.GetAllBatches();
+        }
+    }
 
     public async Task ClearAsync()
     {

src/OrleanSpaces/Grains/Directors/BaseDirector.cs

@@ -44,7 +44,19 @@ public override async Task OnActivateAsync(CancellationToken cancellationToken)
         }
     }
 
-    public async Task<ImmutableArray<StoreTuple<TTuple>>> GetAll()
+    public async IAsyncEnumerable<ImmutableArray<StoreTuple<TTuple>>> GetBatch()
+    {
+        foreach (string storeKey in StoreKeys)
+        {
+            Guid storeId = ParseStoreKey(storeKey);
+            var content = await GrainFactory.GetGrain<TStore>(storeKey).GetAll();
+            var result = content.Tuples.Select(tuple => new StoreTuple<TTuple>(storeId, tuple)).ToImmutableArray();
+
+            yield return result;
+        }
+    }
+
+    public async Task<ImmutableArray<StoreTuple<TTuple>>> GetAllBatches()
     {
         List<Task<StoreContent<TTuple>>> tasks = new();
         foreach (string storeKey in StoreKeys)

src/OrleanSpaces/IStoreDirector.cs

@@ -7,7 +7,9 @@ namespace OrleanSpaces;
 internal interface IStoreDirector<T>
      where T : ISpaceTuple
 {
-    [ReadOnly] Task<ImmutableArray<StoreTuple<T>>> GetAll();
+    [ReadOnly] IAsyncEnumerable<ImmutableArray<StoreTuple<T>>> GetBatch();
+    [ReadOnly] Task<ImmutableArray<StoreTuple<T>>> GetAllBatches();
+
     Task<Guid> Insert(TupleAction<T> action);
     Task Remove(TupleAction<T> action);
     Task RemoveAll(Guid agentId);

src/OrleanSpaces/SpaceOptions.cs

@@ -66,6 +66,11 @@ public sealed class SpaceClientOptions
     /// <see cref="ISpaceAgent{T, TTuple, TTemplate}.ReloadAsync"/>, depending on the agent type.
     /// </i></remarks>
     public bool LoadSpaceContentsUponStartup { get; set; } = true;
+
+    /// <summary>
+    /// Defines the way how the space contents (<i>i.e. the tuples</i>) are loaded by the agent.
+    /// </summary>
+    public SpaceLoadingStrategy LoadingStrategy { get; set; } = SpaceLoadingStrategy.Parallel;
 }
 
 /// <summary>
@@ -96,3 +101,22 @@ public enum SpaceKind
     ULong = 262144,
     UShort = 524288
 }
+
+/// <summary>
+/// Strategies for space loading.
+/// </summary>
+public enum SpaceLoadingStrategy
+{
+    /// <summary>
+    /// <para>Content from all partitions are loaded sequentially.</para>
+    /// <para>Results in a longer time to load the space. But ultimately results in less resource contention, and avoids potential <see cref="ThreadPool"/> starvation.</para>
+    /// </summary>
+    /// <remarks><i>Use if fast loading time is not important, and the space is heavily partitioned.</i></remarks>
+    Sequential,
+    /// <summary>
+    /// <para>Content from all partitions are loaded in parallel.</para>
+    /// <para>Results in less resource contention, and avoids potential <see cref="ThreadPool"/> starvation. But ultimately results in a longer time to load the space.</para>
+    /// </summary>
+    /// <remarks><i>Use if fast loading time is important, and the space is not heavily partitioned.</i></remarks>
+    Parallel
+}