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diff --git a/core/src/main/java/com/android/volley/toolbox/ByteArrayPool.java b/core/src/main/java/com/android/volley/toolbox/ByteArrayPool.java
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+/*
+ * Copyright (C) 2012 The Android Open Source Project
+ *
+ * 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.
+ */
+
+package com.android.volley.toolbox;
+
+import java.util.ArrayList;
+import java.util.Collections;
+import java.util.Comparator;
+import java.util.List;
+
+/**
+ * ByteArrayPool is a source and repository of <code>byte[]</code> objects. Its purpose is to supply
+ * those buffers to consumers who need to use them for a short period of time and then dispose of
+ * them. Simply creating and disposing such buffers in the conventional manner can considerable heap
+ * churn and garbage collection delays on Android, which lacks good management of short-lived heap
+ * objects. It may be advantageous to trade off some memory in the form of a permanently allocated
+ * pool of buffers in order to gain heap performance improvements; that is what this class does.
+ *
+ * <p>A good candidate user for this class is something like an I/O system that uses large temporary
+ * <code>byte[]</code> buffers to copy data around. In these use cases, often the consumer wants the
+ * buffer to be a certain minimum size to ensure good performance (e.g. when copying data chunks off
+ * of a stream), but doesn't mind if the buffer is larger than the minimum. Taking this into account
+ * and also to maximize the odds of being able to reuse a recycled buffer, this class is free to
+ * return buffers larger than the requested size. The caller needs to be able to gracefully deal
+ * with getting buffers any size over the minimum.
+ *
+ * <p>If there is not a suitably-sized buffer in its recycling pool when a buffer is requested, this
+ * class will allocate a new buffer and return it.
+ *
+ * <p>This class has no special ownership of buffers it creates; the caller is free to take a buffer
+ * it receives from this pool, use it permanently, and never return it to the pool; additionally, it
+ * is not harmful to return to this pool a buffer that was allocated elsewhere, provided there are
+ * no other lingering references to it.
+ *
+ * <p>This class ensures that the total size of the buffers in its recycling pool never exceeds a
+ * certain byte limit. When a buffer is returned that would cause the pool to exceed the limit,
+ * least-recently-used buffers are disposed.
+ */
+public class ByteArrayPool {
+    /** The buffer pool, arranged both by last use and by buffer size */
+    private final List<byte[]> mBuffersByLastUse = new ArrayList<>();
+
+    private final List<byte[]> mBuffersBySize = new ArrayList<>(64);
+
+    /** The total size of the buffers in the pool */
+    private int mCurrentSize = 0;
+
+    /**
+     * The maximum aggregate size of the buffers in the pool. Old buffers are discarded to stay
+     * under this limit.
+     */
+    private final int mSizeLimit;
+
+    /** Compares buffers by size */
+    protected static final Comparator<byte[]> BUF_COMPARATOR =
+            new Comparator<byte[]>() {
+                @Override
+                public int compare(byte[] lhs, byte[] rhs) {
+                    return lhs.length - rhs.length;
+                }
+            };
+
+    /** @param sizeLimit the maximum size of the pool, in bytes */
+    public ByteArrayPool(int sizeLimit) {
+        mSizeLimit = sizeLimit;
+    }
+
+    /**
+     * Returns a buffer from the pool if one is available in the requested size, or allocates a new
+     * one if a pooled one is not available.
+     *
+     * @param len the minimum size, in bytes, of the requested buffer. The returned buffer may be
+     *     larger.
+     * @return a byte[] buffer is always returned.
+     */
+    public synchronized byte[] getBuf(int len) {
+        for (int i = 0; i < mBuffersBySize.size(); i++) {
+            byte[] buf = mBuffersBySize.get(i);
+            if (buf.length >= len) {
+                mCurrentSize -= buf.length;
+                mBuffersBySize.remove(i);
+                mBuffersByLastUse.remove(buf);
+                return buf;
+            }
+        }
+        return new byte[len];
+    }
+
+    /**
+     * Returns a buffer to the pool, throwing away old buffers if the pool would exceed its allotted
+     * size.
+     *
+     * @param buf the buffer to return to the pool.
+     */
+    public synchronized void returnBuf(byte[] buf) {
+        if (buf == null || buf.length > mSizeLimit) {
+            return;
+        }
+        mBuffersByLastUse.add(buf);
+        int pos = Collections.binarySearch(mBuffersBySize, buf, BUF_COMPARATOR);
+        if (pos < 0) {
+            pos = -pos - 1;
+        }
+        mBuffersBySize.add(pos, buf);
+        mCurrentSize += buf.length;
+        trim();
+    }
+
+    /** Removes buffers from the pool until it is under its size limit. */
+    private synchronized void trim() {
+        while (mCurrentSize > mSizeLimit) {
+            byte[] buf = mBuffersByLastUse.remove(0);
+            mBuffersBySize.remove(buf);
+            mCurrentSize -= buf.length;
+        }
+    }
+}