/// <summary>
/// Initializes a new ByteBufPool instance with a given segment size and chunk order.
/// If isUnsafe is true, all memory will be allocated from process's heap by using
/// native HeapAlloc API.
/// </summary>
/// <param name="segmentSize">The size of a segment</param>
/// <param name="chunkOrder">Used to caculate chunk size and ensures it is a multiple of a segment size</param>
/// <param name="isUnsafe">Indicates whether allocates memory from process's heap</param>
public ByteBufPool(int segmentSize, int chunkOrder, bool isUnsafe)
{
SegmentSize = segmentSize;
ChunkSize = ValidateAndCalculateChunkSize(segmentSize, chunkOrder);
this.isUnsafe = isUnsafe;
q100 = new ByteBufChunkList(null, 100, int.MaxValue); // No maxUsage for this list. All 100% usage of chunks will be in here.
q075 = new ByteBufChunkList(q100, 75, 100);
q050 = new ByteBufChunkList(q075, 50, 100);
q025 = new ByteBufChunkList(q050, 25, 75);
q000 = new ByteBufChunkList(q025, 1, 50);
qInit = new ByteBufChunkList(q000, int.MinValue, 25); // No minUsage for this list. All new chunks will be inserted to here.
q100.PrevList = q075;
q075.PrevList = q050;
q050.PrevList = q025;
q025.PrevList = q000;
q000.PrevList = null;
qInit.PrevList = qInit;
}
public const int DefaultChunkOrder = 7; // 65536 << 8 = 16 MBytes per chunk
/// <summary>
/// Initializes a new ByteBufPool instance with a given segment size and chunk order.
/// If isUnsafe is true, all memory will be allocated from process's heap by using
/// native HeapAlloc API.
/// </summary>
/// <param name="segmentSize">The size of a segment</param>
/// <param name="chunkOrder">Used to caculate chunk size and ensures it is a multiple of a segment size</param>
/// <param name="isUnsafe">Indicates whether allocates memory from process's heap</param>
public ByteBufPool(int segmentSize, int chunkOrder, bool isUnsafe)
{
SegmentSize = segmentSize;
ChunkSize = ValidateAndCalculateChunkSize(segmentSize, chunkOrder);
this.isUnsafe = isUnsafe;
q100 = new ByteBufChunkList(null, 100, int.MaxValue); // No maxUsage for this list. All 100% usage of chunks will be in here.
q075 = new ByteBufChunkList(q100, 75, 100);
q050 = new ByteBufChunkList(q075, 50, 100);
q025 = new ByteBufChunkList(q050, 25, 75);
q000 = new ByteBufChunkList(q025, 1, 50);
qInit = new ByteBufChunkList(q000, int.MinValue, 25); // No minUsage for this list. All new chunks will be inserted to here.
q100.PrevList = q075;
q075.PrevList = q050;
q050.PrevList = q025;
q025.PrevList = q000;
q000.PrevList = null;
qInit.PrevList = qInit;
}
/// <summary>
/// Initializes a ByteBufChunkList instance with the next ByteBufChunkList and minUsage and maxUsage
/// </summary>
/// <param name="nextList">The next item of this ByteBufChunkList</param>
/// <param name="minUsage">The definition of minimum usage to contain ByteBufChunk</param>
/// <param name="maxUsage">The definition of maximum usage to contain ByteBufChunk</param>
public ByteBufChunkList(ByteBufChunkList nextList, int minUsage, int maxUsage)
{
NextList = nextList;
this.minUsage = minUsage;
this.maxUsage = maxUsage;
}
public void TestAllocateAndFree()
{
var q50 = new ByteBufChunkList(null, 50, 200);
var q00 = new ByteBufChunkList(q50, 1, 50);
q00.PrevList = null;
q50.PrevList = q00;
// This chunk can only allocate 4 ByteBufs totally
var chunk1 = ByteBufChunk.NewChunk(bufPool, bufPool.SegmentSize, bufPool.ChunkSize, false);
var chunk2 = ByteBufChunk.NewChunk(bufPool, bufPool.SegmentSize, bufPool.ChunkSize, false);
var chunk3 = ByteBufChunk.NewChunk(bufPool, bufPool.SegmentSize, bufPool.ChunkSize, false);
//
// Verify Allocate()
//
q00.Add(chunk1);
// Verify the chunk is hosted in q50.
Assert.AreEqual(chunk1.ToString(), q00.ToString());
// Verify allocation success
ByteBuf byteBuf1;
Assert.IsTrue(q00.Allocate(out byteBuf1));
// Verify the chunk be moved to next list.
ByteBuf byteBuf2;
Assert.IsTrue(q00.Allocate(out byteBuf2));
Assert.AreEqual(chunk1.ToString(), q50.ToString()); // chunk1 is in q50 now
// Allocates from q50
ByteBuf byteBuf3;
Assert.IsTrue(q50.Allocate(out byteBuf3));
ByteBuf byteBuf4;
Assert.IsTrue(q50.Allocate(out byteBuf4));
// Verify failed allocation due to chunk 100% usage
ByteBuf byteBuf5;
Assert.AreEqual(100, chunk1.Usage);
Assert.IsFalse(q50.Allocate(out byteBuf5));
// Verify allocation success from chunk2
q50.Add(chunk2);
Assert.IsTrue(q50.Allocate(out byteBuf5));
Assert.AreEqual(chunk2, byteBuf5.ByteBufChunk);
//
// Verify Free()
//
// Build chunk1's chain for Free()
chunk1.Next = chunk3;
chunk3.Prev = chunk1;
// Verify Free() returns false due to chunk2's usage is 0
// that means the chunk need to be destroyed.
Assert.IsFalse(q50.Free(chunk2, byteBuf5));
q50.Add(chunk2);
// Free chunk1 from q50 now.
Assert.IsTrue(q50.Free(chunk1, byteBuf4));
Assert.IsTrue(q50.Free(chunk1, byteBuf3));
Assert.IsTrue(q50.Free(chunk1, byteBuf2));
Assert.AreEqual(chunk1.ToString(), q00.ToString()); // chunk1 is in q00 now
Assert.AreSame(q00, chunk1.Parent);
Assert.AreSame(chunk3, chunk2.Next);
// Free chunk1 from q00 now.
Assert.IsFalse(q00.Free(chunk1, byteBuf1));
Assert.AreEqual("none", q00.ToString()); // q00 is empty now
}
/// <summary>
/// Initializes a ByteBufChunkList instance with the next ByteBufChunkList and minUsage and maxUsage
/// </summary>
/// <param name="nextList">The next item of this ByteBufChunkList</param>
/// <param name="minUsage">The definition of minimum usage to contain ByteBufChunk</param>
/// <param name="maxUsage">The definition of maximum usage to contain ByteBufChunk</param>
public ByteBufChunkList(ByteBufChunkList nextList, int minUsage, int maxUsage)
{
NextList = nextList;
this.minUsage = minUsage;
this.maxUsage = maxUsage;
}