[Internal] Query: Refactors ParallelCrossPartitionQueryPipelineStage to improve perf (#4548)

Maya-Painter · web-flow · commit c5ac103a6375 · 2024-06-18T19:25:44.000Z
* init

* revert test

* remove sw

* nit

* cleanup
diff --git a/Microsoft.Azure.Cosmos/src/Query/Core/Pipeline/CrossPartition/Parallel/ParallelCrossPartitionQueryPipelineStage.cs b/Microsoft.Azure.Cosmos/src/Query/Core/Pipeline/CrossPartition/Parallel/ParallelCrossPartitionQueryPipelineStage.cs
@@ -78,25 +78,24 @@ public async ValueTask<bool> MoveNextAsync(ITrace trace, CancellationToken cance
             else
             {
                 // left most and any non null continuations
-                IOrderedEnumerable<FeedRangeState<QueryState>> feedRangeStates = crossPartitionState
-                    .Value
-                    .ToArray()
-                    .OrderBy(tuple => ((FeedRangeEpk)tuple.FeedRange).Range.Min);
+                FeedRangeState<QueryState>[] feedRangeStates = crossPartitionState.Value.ToArray();
+                Array.Sort<FeedRangeState<QueryState>>(feedRangeStates, (x, y) => string.CompareOrdinal(((FeedRangeEpk)x.FeedRange).Range.Min, ((FeedRangeEpk)y.FeedRange).Range.Min));
 
                 List<ParallelContinuationToken> activeParallelContinuationTokens = new List<ParallelContinuationToken>();
                 {
-                    FeedRangeState<QueryState> firstState = feedRangeStates.First();
+                    FeedRangeState<QueryState> firstState = feedRangeStates[0];
                     ParallelContinuationToken firstParallelContinuationToken = new ParallelContinuationToken(
                         token: firstState.State != null ? ((CosmosString)firstState.State.Value).Value : null,
                         range: ((FeedRangeEpk)firstState.FeedRange).Range);
 
                     activeParallelContinuationTokens.Add(firstParallelContinuationToken);
                 }
 
-                foreach (FeedRangeState<QueryState> feedRangeState in feedRangeStates.Skip(1))
+                for (int i = 1; i < feedRangeStates.Length; i++)
                 {
                     cancellationToken.ThrowIfCancellationRequested();
 
+                    FeedRangeState<QueryState> feedRangeState = feedRangeStates[i];
                     if (feedRangeState.State != null)
                     {
                         ParallelContinuationToken parallelContinuationToken = new ParallelContinuationToken(

Original file line number	Diff line number	Diff line change
`@@ -78,25 +78,24 @@ public async ValueTask<bool> MoveNextAsync(ITrace trace, CancellationToken cance`
`78`	`78`	`else`
`79`	`79`	`{`
`80`	`80`	`// left most and any non null continuations`
`81`		`- IOrderedEnumerable<FeedRangeState<QueryState>> feedRangeStates = crossPartitionState`
`82`		`- .Value`
`83`		`- .ToArray()`
`84`		`- .OrderBy(tuple => ((FeedRangeEpk)tuple.FeedRange).Range.Min);`
	`81`	`+ FeedRangeState<QueryState>[] feedRangeStates = crossPartitionState.Value.ToArray();`
	`82`	`+ Array.Sort<FeedRangeState<QueryState>>(feedRangeStates, (x, y) => string.CompareOrdinal(((FeedRangeEpk)x.FeedRange).Range.Min, ((FeedRangeEpk)y.FeedRange).Range.Min));`
`85`	`83`
`86`	`84`	`List<ParallelContinuationToken> activeParallelContinuationTokens = new List<ParallelContinuationToken>();`
`87`	`85`	`{`
`88`		`- FeedRangeState<QueryState> firstState = feedRangeStates.First();`
	`86`	`+ FeedRangeState<QueryState> firstState = feedRangeStates[0];`
`89`	`87`	`ParallelContinuationToken firstParallelContinuationToken = new ParallelContinuationToken(`
`90`	`88`	`token: firstState.State != null ? ((CosmosString)firstState.State.Value).Value : null,`
`91`	`89`	`range: ((FeedRangeEpk)firstState.FeedRange).Range);`
`92`	`90`
`93`	`91`	`activeParallelContinuationTokens.Add(firstParallelContinuationToken);`
`94`	`92`	`}`
`95`	`93`
`96`		`- foreach (FeedRangeState<QueryState> feedRangeState in feedRangeStates.Skip(1))`
	`94`	`+ for (int i = 1; i < feedRangeStates.Length; i++)`
`97`	`95`	`{`
`98`	`96`	`cancellationToken.ThrowIfCancellationRequested();`
`99`	`97`
	`98`	`+ FeedRangeState<QueryState> feedRangeState = feedRangeStates[i];`
`100`	`99`	`if (feedRangeState.State != null)`
`101`	`100`	`{`
`102`	`101`	`ParallelContinuationToken parallelContinuationToken = new ParallelContinuationToken(`