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diff --git a/src/csharp/Grpc.Core/Internal/DefaultObjectPool.cs b/src/csharp/Grpc.Core/Internal/DefaultObjectPool.cs
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+#region Copyright notice and license
+
+// Copyright 2017 gRPC authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+#endregion
+
+using System;
+using System.Threading;
+using System.Collections.Generic;
+using Grpc.Core.Utils;
+
+namespace Grpc.Core.Internal
+{
+    /// <summary>
+    /// Pool of objects that combines a shared pool and a thread local pool.
+    /// </summary>
+    internal class DefaultObjectPool<T> : IObjectPool<T>
+        where T : class, IDisposable
+    {
+        readonly object myLock = new object();
+        readonly Func<T> itemFactory;
+
+        // Queue shared between threads, access needs to be synchronized.
+        readonly Queue<T> sharedQueue;
+        readonly int sharedCapacity;
+
+        readonly ThreadLocal<ThreadLocalData> threadLocalData;
+        readonly int threadLocalCapacity;
+        readonly int rentLimit;
+
+        bool disposed;
+
+        /// <summary>
+        /// Initializes a new instance of <c>DefaultObjectPool</c> with given shared capacity and thread local capacity.
+        /// Thread local capacity should be significantly smaller than the shared capacity as we don't guarantee immediately
+        /// disposing the objects in the thread local pool after this pool is disposed (they will eventually be garbage collected
+        /// after the thread that owns them has finished).
+        /// On average, the shared pool will only be accessed approx. once for every <c>threadLocalCapacity / 2</c> rent or lease
+        /// operations.
+        /// </summary>
+        public DefaultObjectPool(Func<T> itemFactory, int sharedCapacity, int threadLocalCapacity)
+        {
+            GrpcPreconditions.CheckArgument(sharedCapacity >= 0);
+            GrpcPreconditions.CheckArgument(threadLocalCapacity >= 0);
+            this.itemFactory = GrpcPreconditions.CheckNotNull(itemFactory, nameof(itemFactory));
+            this.sharedQueue = new Queue<T>(sharedCapacity);
+            this.sharedCapacity = sharedCapacity;
+            this.threadLocalData = new ThreadLocal<ThreadLocalData>(() => new ThreadLocalData(threadLocalCapacity), false);
+            this.threadLocalCapacity = threadLocalCapacity;
+            this.rentLimit = threadLocalCapacity != 1 ? threadLocalCapacity / 2 : 1;
+        }
+
+        /// <summary>
+        /// Leases an item from the pool or creates a new instance if the pool is empty.
+        /// Attempts to retrieve the item from the thread local pool first.
+        /// If the thread local pool is empty, the item is taken from the shared pool
+        /// along with more items that are moved to the thread local pool to avoid
+        /// prevent acquiring the lock for shared pool too often.
+        /// The methods should not be called after the pool is disposed, but it won't
+        /// results in an error to do so (after depleting the items potentially left
+        /// in the thread local pool, it will continue returning new objects created by the factory).
+        /// </summary>
+        public T Lease()
+        {
+            var localData = threadLocalData.Value;
+            if (localData.Queue.Count > 0)
+            {
+                return localData.Queue.Dequeue();
+            }
+            if (localData.CreateBudget > 0)
+            {
+                localData.CreateBudget --;
+                return itemFactory();
+            }
+
+            int itemsMoved = 0;
+            T leasedItem = null;
+            lock(myLock)
+            {
+                if (sharedQueue.Count > 0)
+                {
+                    leasedItem = sharedQueue.Dequeue();
+                }
+                while (sharedQueue.Count > 0 && itemsMoved < rentLimit)
+                {
+                    localData.Queue.Enqueue(sharedQueue.Dequeue());
+                    itemsMoved ++;
+                }
+            }
+
+            // If the shared pool didn't contain all rentLimit items,
+            // next time we try to lease we will just create those
+            // instead of trying to grab them from the shared queue.
+            // This is to guarantee we won't be accessing the shared queue too often.
+            localData.CreateBudget = rentLimit - itemsMoved;
+
+            return leasedItem ?? itemFactory();
+        }
+
+        /// <summary>
+        /// Returns an item to the pool.
+        /// Attempts to add the item to the thread local pool first.
+        /// If the thread local pool is full, item is added to a shared pool,
+        /// along with half of the items for the thread local pool, which
+        /// should prevent acquiring the lock for shared pool too often.
+        /// If called after the pool is disposed, we make best effort not to
+        /// add anything to the thread local pool and we guarantee not to add
+        /// anything to the shared pool (items will be disposed instead).
+        /// </summary>
+        public void Return(T item)
+        {
+            GrpcPreconditions.CheckNotNull(item);
+
+            var localData = threadLocalData.Value;
+            if (localData.Queue.Count < threadLocalCapacity && !disposed)
+            {
+                localData.Queue.Enqueue(item);
+                return;
+            }
+            if (localData.DisposeBudget > 0)
+            {
+                localData.DisposeBudget --;
+                item.Dispose();
+                return;
+            }
+
+            int itemsReturned = 0;
+            int returnLimit = rentLimit + 1;
+            lock (myLock)
+            {
+                if (sharedQueue.Count < sharedCapacity && !disposed)
+                {
+                    sharedQueue.Enqueue(item);
+                    itemsReturned ++;
+                }
+                while (sharedQueue.Count < sharedCapacity && itemsReturned < returnLimit && !disposed)
+                {
+                    sharedQueue.Enqueue(localData.Queue.Dequeue());
+                    itemsReturned ++;
+                }
+            }
+
+            // If the shared pool could not accomodate all returnLimit items,
+            // next time we try to return we will just dispose the item
+            // instead of trying to return them to the shared queue.
+            // This is to guarantee we won't be accessing the shared queue too often.
+            localData.DisposeBudget = returnLimit - itemsReturned;
+
+            if (itemsReturned == 0)
+            {
+                localData.DisposeBudget --;
+                item.Dispose();
+            }
+        }
+
+        public void Dispose()
+        {
+            lock (myLock)
+            {
+                if (!disposed)
+                {
+                    disposed = true;
+
+                    while (sharedQueue.Count > 0)
+                    {
+                        sharedQueue.Dequeue().Dispose();
+                    }
+                }
+            }
+        }
+
+        class ThreadLocalData
+        {
+            public ThreadLocalData(int capacity)
+            {
+                this.Queue = new Queue<T>(capacity);
+            }
+
+            public Queue<T> Queue { get; }
+            public int CreateBudget { get; set; }
+            public int DisposeBudget { get; set; }
+        }
+    }
+}