From eb2230d65ad3f968052353c715af157794121dce Mon Sep 17 00:00:00 2001
From: Aleksei Smirnov <tlalok@inbox.ru>
Date: Fri, 8 Sep 2023 20:36:06 +0300
Subject: [PATCH 1/8] Optimize PrimitiveColumnContainer.Clone method

---
 src/Microsoft.Data.Analysis/DataFrameBuffer.cs    |  3 ++-
 .../PrimitiveColumnContainer.cs                   | 15 +++------------
 test/Microsoft.Data.Analysis.Tests/BufferTests.cs | 15 ++++++++++++++-
 3 files changed, 19 insertions(+), 14 deletions(-)

diff --git a/src/Microsoft.Data.Analysis/DataFrameBuffer.cs b/src/Microsoft.Data.Analysis/DataFrameBuffer.cs
index e4ee20f9b6..a22f94c56d 100644
--- a/src/Microsoft.Data.Analysis/DataFrameBuffer.cs
+++ b/src/Microsoft.Data.Analysis/DataFrameBuffer.cs
@@ -38,10 +38,11 @@ public Span<T> RawSpan
 
         public DataFrameBuffer(int numberOfValues = 8) : base(numberOfValues) { }
 
-        internal DataFrameBuffer(ReadOnlyMemory<byte> buffer, int length) : base(buffer, length)
+        internal DataFrameBuffer(ReadOnlyMemory<byte> buffer, int length)
         {
             _memory = new byte[buffer.Length];
             buffer.CopyTo(_memory);
+            Length = length;
         }
 
         public void Append(T value)
diff --git a/src/Microsoft.Data.Analysis/PrimitiveColumnContainer.cs b/src/Microsoft.Data.Analysis/PrimitiveColumnContainer.cs
index 1e37ac2206..aa713a66c5 100644
--- a/src/Microsoft.Data.Analysis/PrimitiveColumnContainer.cs
+++ b/src/Microsoft.Data.Analysis/PrimitiveColumnContainer.cs
@@ -9,6 +9,7 @@
 using System.Runtime.CompilerServices;
 using System.Runtime.InteropServices;
 using System.Text;
+using Microsoft.ML.Data;
 
 namespace Microsoft.Data.Analysis
 {
@@ -436,13 +437,8 @@ private List<ReadOnlyDataFrameBuffer<byte>> CloneNullBitMapBuffers()
             List<ReadOnlyDataFrameBuffer<byte>> ret = new List<ReadOnlyDataFrameBuffer<byte>>();
             foreach (ReadOnlyDataFrameBuffer<byte> buffer in NullBitMapBuffers)
             {
-                DataFrameBuffer<byte> newBuffer = new DataFrameBuffer<byte>();
+                DataFrameBuffer<byte> newBuffer = new DataFrameBuffer<byte>(buffer.ReadOnlyBuffer, buffer.Length);
                 ret.Add(newBuffer);
-                ReadOnlySpan<byte> span = buffer.ReadOnlySpan;
-                for (int i = 0; i < span.Length; i++)
-                {
-                    newBuffer.Append(span[i]);
-                }
             }
             return ret;
         }
@@ -518,14 +514,9 @@ public PrimitiveColumnContainer<T> Clone()
             var ret = new PrimitiveColumnContainer<T>();
             foreach (ReadOnlyDataFrameBuffer<T> buffer in Buffers)
             {
-                DataFrameBuffer<T> newBuffer = new DataFrameBuffer<T>();
+                DataFrameBuffer<T> newBuffer = new DataFrameBuffer<T>(buffer.ReadOnlyBuffer, buffer.Length);
                 ret.Buffers.Add(newBuffer);
-                ReadOnlySpan<T> span = buffer.ReadOnlySpan;
                 ret.Length += buffer.Length;
-                for (int i = 0; i < span.Length; i++)
-                {
-                    newBuffer.Append(span[i]);
-                }
             }
             ret.NullBitMapBuffers = CloneNullBitMapBuffers();
             ret.NullCount = NullCount;
diff --git a/test/Microsoft.Data.Analysis.Tests/BufferTests.cs b/test/Microsoft.Data.Analysis.Tests/BufferTests.cs
index bc8f66d822..3a88e2eddc 100644
--- a/test/Microsoft.Data.Analysis.Tests/BufferTests.cs
+++ b/test/Microsoft.Data.Analysis.Tests/BufferTests.cs
@@ -79,7 +79,6 @@ public void TestNullCounts()
             Assert.Equal(2, intColumn[3]);
             Assert.Null(intColumn[4]);
             Assert.Equal(3, intColumn[5]);
-
         }
 
         [Fact]
@@ -134,6 +133,20 @@ public void TestAppendMany()
             Assert.False(intColumn.IsValid(7));
         }
 
+        [Fact]
+        public void TestClone()
+        {
+            PrimitiveDataFrameColumn<int> intColumn = new PrimitiveDataFrameColumn<int>("Int1", new int?[] { 1, 2, 3, 4, null });
+            var copy = intColumn.Clone();
+
+            Assert.Equal(intColumn.Name, copy.Name);
+            Assert.Equal(intColumn.Length, copy.Length);
+            Assert.Equal(intColumn.DataType, copy.DataType);
+
+            for (int i = 0; i < intColumn.Length; i++)
+                Assert.Equal(intColumn[i], copy[i]);
+        }
+
         [Fact]
         public void TestBasicArrowStringColumn()
         {

From 67af2766bdc0dd931d0ada2232cde6175d13e897 Mon Sep 17 00:00:00 2001
From: Aleksei Smirnov <tlalok@inbox.ru>
Date: Fri, 8 Sep 2023 21:22:35 +0300
Subject: [PATCH 2/8] Avoid unnecessary type conversion during binary
 operations

---
 ...BinaryOperationImplementations.Exploded.cs | 70 +++++++++----------
 ...BinaryOperationImplementations.Exploded.tt |  2 +-
 2 files changed, 36 insertions(+), 36 deletions(-)

diff --git a/src/Microsoft.Data.Analysis/PrimitiveDataFrameColumn.BinaryOperationImplementations.Exploded.cs b/src/Microsoft.Data.Analysis/PrimitiveDataFrameColumn.BinaryOperationImplementations.Exploded.cs
index ac8035f0ba..6a54acb85e 100644
--- a/src/Microsoft.Data.Analysis/PrimitiveDataFrameColumn.BinaryOperationImplementations.Exploded.cs
+++ b/src/Microsoft.Data.Analysis/PrimitiveDataFrameColumn.BinaryOperationImplementations.Exploded.cs
@@ -19,7 +19,7 @@ internal DecimalDataFrameColumn AddImplementation(DecimalDataFrameColumn column,
             {
                 throw new ArgumentException(Strings.MismatchedColumnLengths, nameof(column));
             }
-            DecimalDataFrameColumn newColumn = inPlace ? this : CloneAsDecimalColumn();
+            DecimalDataFrameColumn newColumn = inPlace ? this : (DecimalDataFrameColumn)Clone();
             newColumn.ColumnContainer.Add(column.ColumnContainer);
             return newColumn;
         }
@@ -32,7 +32,7 @@ internal DoubleDataFrameColumn AddImplementation(DoubleDataFrameColumn column, b
             {
                 throw new ArgumentException(Strings.MismatchedColumnLengths, nameof(column));
             }
-            DoubleDataFrameColumn newColumn = inPlace ? this : CloneAsDoubleColumn();
+            DoubleDataFrameColumn newColumn = inPlace ? this : (DoubleDataFrameColumn)Clone();
             newColumn.ColumnContainer.Add(column.ColumnContainer);
             return newColumn;
         }
@@ -45,7 +45,7 @@ internal SingleDataFrameColumn AddImplementation(SingleDataFrameColumn column, b
             {
                 throw new ArgumentException(Strings.MismatchedColumnLengths, nameof(column));
             }
-            SingleDataFrameColumn newColumn = inPlace ? this : CloneAsSingleColumn();
+            SingleDataFrameColumn newColumn = inPlace ? this : (SingleDataFrameColumn)Clone();
             newColumn.ColumnContainer.Add(column.ColumnContainer);
             return newColumn;
         }
@@ -58,7 +58,7 @@ internal Int32DataFrameColumn AddImplementation(Int32DataFrameColumn column, boo
             {
                 throw new ArgumentException(Strings.MismatchedColumnLengths, nameof(column));
             }
-            Int32DataFrameColumn newColumn = inPlace ? this : CloneAsInt32Column();
+            Int32DataFrameColumn newColumn = inPlace ? this : (Int32DataFrameColumn)Clone();
             newColumn.ColumnContainer.Add(column.ColumnContainer);
             return newColumn;
         }
@@ -71,7 +71,7 @@ internal Int64DataFrameColumn AddImplementation(Int64DataFrameColumn column, boo
             {
                 throw new ArgumentException(Strings.MismatchedColumnLengths, nameof(column));
             }
-            Int64DataFrameColumn newColumn = inPlace ? this : CloneAsInt64Column();
+            Int64DataFrameColumn newColumn = inPlace ? this : (Int64DataFrameColumn)Clone();
             newColumn.ColumnContainer.Add(column.ColumnContainer);
             return newColumn;
         }
@@ -84,7 +84,7 @@ internal UInt32DataFrameColumn AddImplementation(UInt32DataFrameColumn column, b
             {
                 throw new ArgumentException(Strings.MismatchedColumnLengths, nameof(column));
             }
-            UInt32DataFrameColumn newColumn = inPlace ? this : CloneAsUInt32Column();
+            UInt32DataFrameColumn newColumn = inPlace ? this : (UInt32DataFrameColumn)Clone();
             newColumn.ColumnContainer.Add(column.ColumnContainer);
             return newColumn;
         }
@@ -97,7 +97,7 @@ internal UInt64DataFrameColumn AddImplementation(UInt64DataFrameColumn column, b
             {
                 throw new ArgumentException(Strings.MismatchedColumnLengths, nameof(column));
             }
-            UInt64DataFrameColumn newColumn = inPlace ? this : CloneAsUInt64Column();
+            UInt64DataFrameColumn newColumn = inPlace ? this : (UInt64DataFrameColumn)Clone();
             newColumn.ColumnContainer.Add(column.ColumnContainer);
             return newColumn;
         }
@@ -250,7 +250,7 @@ internal DecimalDataFrameColumn SubtractImplementation(DecimalDataFrameColumn co
             {
                 throw new ArgumentException(Strings.MismatchedColumnLengths, nameof(column));
             }
-            DecimalDataFrameColumn newColumn = inPlace ? this : CloneAsDecimalColumn();
+            DecimalDataFrameColumn newColumn = inPlace ? this : (DecimalDataFrameColumn)Clone();
             newColumn.ColumnContainer.Subtract(column.ColumnContainer);
             return newColumn;
         }
@@ -263,7 +263,7 @@ internal DoubleDataFrameColumn SubtractImplementation(DoubleDataFrameColumn colu
             {
                 throw new ArgumentException(Strings.MismatchedColumnLengths, nameof(column));
             }
-            DoubleDataFrameColumn newColumn = inPlace ? this : CloneAsDoubleColumn();
+            DoubleDataFrameColumn newColumn = inPlace ? this : (DoubleDataFrameColumn)Clone();
             newColumn.ColumnContainer.Subtract(column.ColumnContainer);
             return newColumn;
         }
@@ -276,7 +276,7 @@ internal SingleDataFrameColumn SubtractImplementation(SingleDataFrameColumn colu
             {
                 throw new ArgumentException(Strings.MismatchedColumnLengths, nameof(column));
             }
-            SingleDataFrameColumn newColumn = inPlace ? this : CloneAsSingleColumn();
+            SingleDataFrameColumn newColumn = inPlace ? this : (SingleDataFrameColumn)Clone();
             newColumn.ColumnContainer.Subtract(column.ColumnContainer);
             return newColumn;
         }
@@ -289,7 +289,7 @@ internal Int32DataFrameColumn SubtractImplementation(Int32DataFrameColumn column
             {
                 throw new ArgumentException(Strings.MismatchedColumnLengths, nameof(column));
             }
-            Int32DataFrameColumn newColumn = inPlace ? this : CloneAsInt32Column();
+            Int32DataFrameColumn newColumn = inPlace ? this : (Int32DataFrameColumn)Clone();
             newColumn.ColumnContainer.Subtract(column.ColumnContainer);
             return newColumn;
         }
@@ -302,7 +302,7 @@ internal Int64DataFrameColumn SubtractImplementation(Int64DataFrameColumn column
             {
                 throw new ArgumentException(Strings.MismatchedColumnLengths, nameof(column));
             }
-            Int64DataFrameColumn newColumn = inPlace ? this : CloneAsInt64Column();
+            Int64DataFrameColumn newColumn = inPlace ? this : (Int64DataFrameColumn)Clone();
             newColumn.ColumnContainer.Subtract(column.ColumnContainer);
             return newColumn;
         }
@@ -315,7 +315,7 @@ internal UInt32DataFrameColumn SubtractImplementation(UInt32DataFrameColumn colu
             {
                 throw new ArgumentException(Strings.MismatchedColumnLengths, nameof(column));
             }
-            UInt32DataFrameColumn newColumn = inPlace ? this : CloneAsUInt32Column();
+            UInt32DataFrameColumn newColumn = inPlace ? this : (UInt32DataFrameColumn)Clone();
             newColumn.ColumnContainer.Subtract(column.ColumnContainer);
             return newColumn;
         }
@@ -328,7 +328,7 @@ internal UInt64DataFrameColumn SubtractImplementation(UInt64DataFrameColumn colu
             {
                 throw new ArgumentException(Strings.MismatchedColumnLengths, nameof(column));
             }
-            UInt64DataFrameColumn newColumn = inPlace ? this : CloneAsUInt64Column();
+            UInt64DataFrameColumn newColumn = inPlace ? this : (UInt64DataFrameColumn)Clone();
             newColumn.ColumnContainer.Subtract(column.ColumnContainer);
             return newColumn;
         }
@@ -481,7 +481,7 @@ internal DecimalDataFrameColumn MultiplyImplementation(DecimalDataFrameColumn co
             {
                 throw new ArgumentException(Strings.MismatchedColumnLengths, nameof(column));
             }
-            DecimalDataFrameColumn newColumn = inPlace ? this : CloneAsDecimalColumn();
+            DecimalDataFrameColumn newColumn = inPlace ? this : (DecimalDataFrameColumn)Clone();
             newColumn.ColumnContainer.Multiply(column.ColumnContainer);
             return newColumn;
         }
@@ -494,7 +494,7 @@ internal DoubleDataFrameColumn MultiplyImplementation(DoubleDataFrameColumn colu
             {
                 throw new ArgumentException(Strings.MismatchedColumnLengths, nameof(column));
             }
-            DoubleDataFrameColumn newColumn = inPlace ? this : CloneAsDoubleColumn();
+            DoubleDataFrameColumn newColumn = inPlace ? this : (DoubleDataFrameColumn)Clone();
             newColumn.ColumnContainer.Multiply(column.ColumnContainer);
             return newColumn;
         }
@@ -507,7 +507,7 @@ internal SingleDataFrameColumn MultiplyImplementation(SingleDataFrameColumn colu
             {
                 throw new ArgumentException(Strings.MismatchedColumnLengths, nameof(column));
             }
-            SingleDataFrameColumn newColumn = inPlace ? this : CloneAsSingleColumn();
+            SingleDataFrameColumn newColumn = inPlace ? this : (SingleDataFrameColumn)Clone();
             newColumn.ColumnContainer.Multiply(column.ColumnContainer);
             return newColumn;
         }
@@ -520,7 +520,7 @@ internal Int32DataFrameColumn MultiplyImplementation(Int32DataFrameColumn column
             {
                 throw new ArgumentException(Strings.MismatchedColumnLengths, nameof(column));
             }
-            Int32DataFrameColumn newColumn = inPlace ? this : CloneAsInt32Column();
+            Int32DataFrameColumn newColumn = inPlace ? this : (Int32DataFrameColumn)Clone();
             newColumn.ColumnContainer.Multiply(column.ColumnContainer);
             return newColumn;
         }
@@ -533,7 +533,7 @@ internal Int64DataFrameColumn MultiplyImplementation(Int64DataFrameColumn column
             {
                 throw new ArgumentException(Strings.MismatchedColumnLengths, nameof(column));
             }
-            Int64DataFrameColumn newColumn = inPlace ? this : CloneAsInt64Column();
+            Int64DataFrameColumn newColumn = inPlace ? this : (Int64DataFrameColumn)Clone();
             newColumn.ColumnContainer.Multiply(column.ColumnContainer);
             return newColumn;
         }
@@ -546,7 +546,7 @@ internal UInt32DataFrameColumn MultiplyImplementation(UInt32DataFrameColumn colu
             {
                 throw new ArgumentException(Strings.MismatchedColumnLengths, nameof(column));
             }
-            UInt32DataFrameColumn newColumn = inPlace ? this : CloneAsUInt32Column();
+            UInt32DataFrameColumn newColumn = inPlace ? this : (UInt32DataFrameColumn)Clone();
             newColumn.ColumnContainer.Multiply(column.ColumnContainer);
             return newColumn;
         }
@@ -559,7 +559,7 @@ internal UInt64DataFrameColumn MultiplyImplementation(UInt64DataFrameColumn colu
             {
                 throw new ArgumentException(Strings.MismatchedColumnLengths, nameof(column));
             }
-            UInt64DataFrameColumn newColumn = inPlace ? this : CloneAsUInt64Column();
+            UInt64DataFrameColumn newColumn = inPlace ? this : (UInt64DataFrameColumn)Clone();
             newColumn.ColumnContainer.Multiply(column.ColumnContainer);
             return newColumn;
         }
@@ -712,7 +712,7 @@ internal DecimalDataFrameColumn DivideImplementation(DecimalDataFrameColumn colu
             {
                 throw new ArgumentException(Strings.MismatchedColumnLengths, nameof(column));
             }
-            DecimalDataFrameColumn newColumn = inPlace ? this : CloneAsDecimalColumn();
+            DecimalDataFrameColumn newColumn = inPlace ? this : (DecimalDataFrameColumn)Clone();
             newColumn.ColumnContainer.Divide(column.ColumnContainer);
             return newColumn;
         }
@@ -725,7 +725,7 @@ internal DoubleDataFrameColumn DivideImplementation(DoubleDataFrameColumn column
             {
                 throw new ArgumentException(Strings.MismatchedColumnLengths, nameof(column));
             }
-            DoubleDataFrameColumn newColumn = inPlace ? this : CloneAsDoubleColumn();
+            DoubleDataFrameColumn newColumn = inPlace ? this : (DoubleDataFrameColumn)Clone();
             newColumn.ColumnContainer.Divide(column.ColumnContainer);
             return newColumn;
         }
@@ -738,7 +738,7 @@ internal SingleDataFrameColumn DivideImplementation(SingleDataFrameColumn column
             {
                 throw new ArgumentException(Strings.MismatchedColumnLengths, nameof(column));
             }
-            SingleDataFrameColumn newColumn = inPlace ? this : CloneAsSingleColumn();
+            SingleDataFrameColumn newColumn = inPlace ? this : (SingleDataFrameColumn)Clone();
             newColumn.ColumnContainer.Divide(column.ColumnContainer);
             return newColumn;
         }
@@ -751,7 +751,7 @@ internal Int32DataFrameColumn DivideImplementation(Int32DataFrameColumn column,
             {
                 throw new ArgumentException(Strings.MismatchedColumnLengths, nameof(column));
             }
-            Int32DataFrameColumn newColumn = inPlace ? this : CloneAsInt32Column();
+            Int32DataFrameColumn newColumn = inPlace ? this : (Int32DataFrameColumn)Clone();
             newColumn.ColumnContainer.Divide(column.ColumnContainer);
             return newColumn;
         }
@@ -764,7 +764,7 @@ internal Int64DataFrameColumn DivideImplementation(Int64DataFrameColumn column,
             {
                 throw new ArgumentException(Strings.MismatchedColumnLengths, nameof(column));
             }
-            Int64DataFrameColumn newColumn = inPlace ? this : CloneAsInt64Column();
+            Int64DataFrameColumn newColumn = inPlace ? this : (Int64DataFrameColumn)Clone();
             newColumn.ColumnContainer.Divide(column.ColumnContainer);
             return newColumn;
         }
@@ -777,7 +777,7 @@ internal UInt32DataFrameColumn DivideImplementation(UInt32DataFrameColumn column
             {
                 throw new ArgumentException(Strings.MismatchedColumnLengths, nameof(column));
             }
-            UInt32DataFrameColumn newColumn = inPlace ? this : CloneAsUInt32Column();
+            UInt32DataFrameColumn newColumn = inPlace ? this : (UInt32DataFrameColumn)Clone();
             newColumn.ColumnContainer.Divide(column.ColumnContainer);
             return newColumn;
         }
@@ -790,7 +790,7 @@ internal UInt64DataFrameColumn DivideImplementation(UInt64DataFrameColumn column
             {
                 throw new ArgumentException(Strings.MismatchedColumnLengths, nameof(column));
             }
-            UInt64DataFrameColumn newColumn = inPlace ? this : CloneAsUInt64Column();
+            UInt64DataFrameColumn newColumn = inPlace ? this : (UInt64DataFrameColumn)Clone();
             newColumn.ColumnContainer.Divide(column.ColumnContainer);
             return newColumn;
         }
@@ -943,7 +943,7 @@ internal DecimalDataFrameColumn ModuloImplementation(DecimalDataFrameColumn colu
             {
                 throw new ArgumentException(Strings.MismatchedColumnLengths, nameof(column));
             }
-            DecimalDataFrameColumn newColumn = inPlace ? this : CloneAsDecimalColumn();
+            DecimalDataFrameColumn newColumn = inPlace ? this : (DecimalDataFrameColumn)Clone();
             newColumn.ColumnContainer.Modulo(column.ColumnContainer);
             return newColumn;
         }
@@ -956,7 +956,7 @@ internal DoubleDataFrameColumn ModuloImplementation(DoubleDataFrameColumn column
             {
                 throw new ArgumentException(Strings.MismatchedColumnLengths, nameof(column));
             }
-            DoubleDataFrameColumn newColumn = inPlace ? this : CloneAsDoubleColumn();
+            DoubleDataFrameColumn newColumn = inPlace ? this : (DoubleDataFrameColumn)Clone();
             newColumn.ColumnContainer.Modulo(column.ColumnContainer);
             return newColumn;
         }
@@ -969,7 +969,7 @@ internal SingleDataFrameColumn ModuloImplementation(SingleDataFrameColumn column
             {
                 throw new ArgumentException(Strings.MismatchedColumnLengths, nameof(column));
             }
-            SingleDataFrameColumn newColumn = inPlace ? this : CloneAsSingleColumn();
+            SingleDataFrameColumn newColumn = inPlace ? this : (SingleDataFrameColumn)Clone();
             newColumn.ColumnContainer.Modulo(column.ColumnContainer);
             return newColumn;
         }
@@ -982,7 +982,7 @@ internal Int32DataFrameColumn ModuloImplementation(Int32DataFrameColumn column,
             {
                 throw new ArgumentException(Strings.MismatchedColumnLengths, nameof(column));
             }
-            Int32DataFrameColumn newColumn = inPlace ? this : CloneAsInt32Column();
+            Int32DataFrameColumn newColumn = inPlace ? this : (Int32DataFrameColumn)Clone();
             newColumn.ColumnContainer.Modulo(column.ColumnContainer);
             return newColumn;
         }
@@ -995,7 +995,7 @@ internal Int64DataFrameColumn ModuloImplementation(Int64DataFrameColumn column,
             {
                 throw new ArgumentException(Strings.MismatchedColumnLengths, nameof(column));
             }
-            Int64DataFrameColumn newColumn = inPlace ? this : CloneAsInt64Column();
+            Int64DataFrameColumn newColumn = inPlace ? this : (Int64DataFrameColumn)Clone();
             newColumn.ColumnContainer.Modulo(column.ColumnContainer);
             return newColumn;
         }
@@ -1008,7 +1008,7 @@ internal UInt32DataFrameColumn ModuloImplementation(UInt32DataFrameColumn column
             {
                 throw new ArgumentException(Strings.MismatchedColumnLengths, nameof(column));
             }
-            UInt32DataFrameColumn newColumn = inPlace ? this : CloneAsUInt32Column();
+            UInt32DataFrameColumn newColumn = inPlace ? this : (UInt32DataFrameColumn)Clone();
             newColumn.ColumnContainer.Modulo(column.ColumnContainer);
             return newColumn;
         }
@@ -1021,7 +1021,7 @@ internal UInt64DataFrameColumn ModuloImplementation(UInt64DataFrameColumn column
             {
                 throw new ArgumentException(Strings.MismatchedColumnLengths, nameof(column));
             }
-            UInt64DataFrameColumn newColumn = inPlace ? this : CloneAsUInt64Column();
+            UInt64DataFrameColumn newColumn = inPlace ? this : (UInt64DataFrameColumn)Clone();
             newColumn.ColumnContainer.Modulo(column.ColumnContainer);
             return newColumn;
         }
diff --git a/src/Microsoft.Data.Analysis/PrimitiveDataFrameColumn.BinaryOperationImplementations.Exploded.tt b/src/Microsoft.Data.Analysis/PrimitiveDataFrameColumn.BinaryOperationImplementations.Exploded.tt
index 001aab32b1..89eede1a0c 100644
--- a/src/Microsoft.Data.Analysis/PrimitiveDataFrameColumn.BinaryOperationImplementations.Exploded.tt
+++ b/src/Microsoft.Data.Analysis/PrimitiveDataFrameColumn.BinaryOperationImplementations.Exploded.tt
@@ -76,7 +76,7 @@ void GenerateAllBinaryCombinationsForMethod(string inputMethodName)
             {
                 throw new ArgumentException(Strings.MismatchedColumnLengths, nameof(column));
             }
-            <#=fullReturnType#> newColumn = inPlace ? this : CloneAs<#=capitalizedReturnType#>Column();
+            <#=fullReturnType#> newColumn = inPlace ? this : (<#=fullReturnType#>)Clone();
             newColumn.ColumnContainer.<#=inputMethodName#>(column.ColumnContainer);
             return newColumn;
         }

From cbc7c4d512e960d30fead475b59798161691f749 Mon Sep 17 00:00:00 2001
From: Aleksei Smirnov <tlalok@inbox.ru>
Date: Fri, 8 Sep 2023 22:02:06 +0300
Subject: [PATCH 3/8] Remove using

---
 src/Microsoft.Data.Analysis/PrimitiveColumnContainer.cs | 1 -
 1 file changed, 1 deletion(-)

diff --git a/src/Microsoft.Data.Analysis/PrimitiveColumnContainer.cs b/src/Microsoft.Data.Analysis/PrimitiveColumnContainer.cs
index aa713a66c5..627efdea26 100644
--- a/src/Microsoft.Data.Analysis/PrimitiveColumnContainer.cs
+++ b/src/Microsoft.Data.Analysis/PrimitiveColumnContainer.cs
@@ -9,7 +9,6 @@
 using System.Runtime.CompilerServices;
 using System.Runtime.InteropServices;
 using System.Text;
-using Microsoft.ML.Data;
 
 namespace Microsoft.Data.Analysis
 {

From 63d983a1a26789136dfe660db95a561d85132609 Mon Sep 17 00:00:00 2001
From: Aleksei Smirnov <tlalok@inbox.ru>
Date: Sat, 9 Sep 2023 09:05:54 +0300
Subject: [PATCH 4/8] Fix DataFrameBuffer constructor

---
 .../DataFrameBuffer.cs                        | 11 +++++-
 .../PrimitiveColumnContainer.cs               | 37 +++++++------------
 2 files changed, 23 insertions(+), 25 deletions(-)

diff --git a/src/Microsoft.Data.Analysis/DataFrameBuffer.cs b/src/Microsoft.Data.Analysis/DataFrameBuffer.cs
index a22f94c56d..c0f2af2f4c 100644
--- a/src/Microsoft.Data.Analysis/DataFrameBuffer.cs
+++ b/src/Microsoft.Data.Analysis/DataFrameBuffer.cs
@@ -5,6 +5,7 @@
 using System;
 using System.Runtime.CompilerServices;
 using System.Runtime.InteropServices;
+using Microsoft.ML.Data;
 
 namespace Microsoft.Data.Analysis
 {
@@ -36,7 +37,15 @@ public Span<T> RawSpan
             get => MemoryMarshal.Cast<byte, T>(Buffer.Span);
         }
 
-        public DataFrameBuffer(int numberOfValues = 8) : base(numberOfValues) { }
+        public DataFrameBuffer(int numberOfValues = 8)
+        {
+            if ((long)numberOfValues * Size > MaxCapacity)
+            {
+                throw new ArgumentException($"{numberOfValues} exceeds buffer capacity", nameof(numberOfValues));
+            }
+
+            _memory = new byte[numberOfValues];
+        }
 
         internal DataFrameBuffer(ReadOnlyMemory<byte> buffer, int length)
         {
diff --git a/src/Microsoft.Data.Analysis/PrimitiveColumnContainer.cs b/src/Microsoft.Data.Analysis/PrimitiveColumnContainer.cs
index 627efdea26..78d58bbca5 100644
--- a/src/Microsoft.Data.Analysis/PrimitiveColumnContainer.cs
+++ b/src/Microsoft.Data.Analysis/PrimitiveColumnContainer.cs
@@ -527,9 +527,9 @@ internal PrimitiveColumnContainer<bool> CloneAsBoolContainer()
             var ret = new PrimitiveColumnContainer<bool>();
             foreach (ReadOnlyDataFrameBuffer<T> buffer in Buffers)
             {
-                DataFrameBuffer<bool> newBuffer = new DataFrameBuffer<bool>();
+                DataFrameBuffer<bool> newBuffer = new DataFrameBuffer<bool>(buffer.Length);
                 ret.Buffers.Add(newBuffer);
-                newBuffer.EnsureCapacity(buffer.Length);
+
                 if (typeof(T) == typeof(bool))
                 {
                     var localBuffer = buffer;
@@ -554,9 +554,8 @@ internal PrimitiveColumnContainer<byte> CloneAsByteContainer()
             foreach (ReadOnlyDataFrameBuffer<T> buffer in Buffers)
             {
                 ret.Length += buffer.Length;
-                DataFrameBuffer<byte> newBuffer = new DataFrameBuffer<byte>();
+                DataFrameBuffer<byte> newBuffer = new DataFrameBuffer<byte>(buffer.Length);
                 ret.Buffers.Add(newBuffer);
-                newBuffer.EnsureCapacity(buffer.Length);
                 ReadOnlySpan<T> span = buffer.ReadOnlySpan;
                 for (int i = 0; i < span.Length; i++)
                 {
@@ -574,9 +573,8 @@ internal PrimitiveColumnContainer<sbyte> CloneAsSByteContainer()
             foreach (ReadOnlyDataFrameBuffer<T> buffer in Buffers)
             {
                 ret.Length += buffer.Length;
-                DataFrameBuffer<sbyte> newBuffer = new DataFrameBuffer<sbyte>();
+                DataFrameBuffer<sbyte> newBuffer = new DataFrameBuffer<sbyte>(buffer.Length);
                 ret.Buffers.Add(newBuffer);
-                newBuffer.EnsureCapacity(buffer.Length);
                 ReadOnlySpan<T> span = buffer.ReadOnlySpan;
                 for (int i = 0; i < span.Length; i++)
                 {
@@ -594,9 +592,8 @@ internal PrimitiveColumnContainer<double> CloneAsDoubleContainer()
             foreach (ReadOnlyDataFrameBuffer<T> buffer in Buffers)
             {
                 ret.Length += buffer.Length;
-                DataFrameBuffer<double> newBuffer = new DataFrameBuffer<double>();
+                DataFrameBuffer<double> newBuffer = new DataFrameBuffer<double>(buffer.Length);
                 ret.Buffers.Add(newBuffer);
-                newBuffer.EnsureCapacity(buffer.Length);
                 ReadOnlySpan<T> span = buffer.ReadOnlySpan;
                 for (int i = 0; i < span.Length; i++)
                 {
@@ -614,9 +611,8 @@ internal PrimitiveColumnContainer<decimal> CloneAsDecimalContainer()
             foreach (ReadOnlyDataFrameBuffer<T> buffer in Buffers)
             {
                 ret.Length += buffer.Length;
-                DataFrameBuffer<decimal> newBuffer = new DataFrameBuffer<decimal>();
+                DataFrameBuffer<decimal> newBuffer = new DataFrameBuffer<decimal>(buffer.Length);
                 ret.Buffers.Add(newBuffer);
-                newBuffer.EnsureCapacity(buffer.Length);
                 ReadOnlySpan<T> span = buffer.ReadOnlySpan;
                 for (int i = 0; i < span.Length; i++)
                 {
@@ -634,9 +630,8 @@ internal PrimitiveColumnContainer<short> CloneAsShortContainer()
             foreach (ReadOnlyDataFrameBuffer<T> buffer in Buffers)
             {
                 ret.Length += buffer.Length;
-                DataFrameBuffer<short> newBuffer = new DataFrameBuffer<short>();
+                DataFrameBuffer<short> newBuffer = new DataFrameBuffer<short>(buffer.Length);
                 ret.Buffers.Add(newBuffer);
-                newBuffer.EnsureCapacity(buffer.Length);
                 ReadOnlySpan<T> span = buffer.ReadOnlySpan;
                 for (int i = 0; i < span.Length; i++)
                 {
@@ -654,9 +649,8 @@ internal PrimitiveColumnContainer<ushort> CloneAsUShortContainer()
             foreach (ReadOnlyDataFrameBuffer<T> buffer in Buffers)
             {
                 ret.Length += buffer.Length;
-                DataFrameBuffer<ushort> newBuffer = new DataFrameBuffer<ushort>();
+                DataFrameBuffer<ushort> newBuffer = new DataFrameBuffer<ushort>(buffer.Length);
                 ret.Buffers.Add(newBuffer);
-                newBuffer.EnsureCapacity(buffer.Length);
                 ReadOnlySpan<T> span = buffer.ReadOnlySpan;
                 for (int i = 0; i < span.Length; i++)
                 {
@@ -674,9 +668,8 @@ internal PrimitiveColumnContainer<int> CloneAsIntContainer()
             foreach (ReadOnlyDataFrameBuffer<T> buffer in Buffers)
             {
                 ret.Length += buffer.Length;
-                DataFrameBuffer<int> newBuffer = new DataFrameBuffer<int>();
+                DataFrameBuffer<int> newBuffer = new DataFrameBuffer<int>(buffer.Length);
                 ret.Buffers.Add(newBuffer);
-                newBuffer.EnsureCapacity(buffer.Length);
                 ReadOnlySpan<T> span = buffer.ReadOnlySpan;
                 for (int i = 0; i < span.Length; i++)
                 {
@@ -694,9 +687,8 @@ internal PrimitiveColumnContainer<uint> CloneAsUIntContainer()
             foreach (ReadOnlyDataFrameBuffer<T> buffer in Buffers)
             {
                 ret.Length += buffer.Length;
-                DataFrameBuffer<uint> newBuffer = new DataFrameBuffer<uint>();
+                DataFrameBuffer<uint> newBuffer = new DataFrameBuffer<uint>(buffer.Length);
                 ret.Buffers.Add(newBuffer);
-                newBuffer.EnsureCapacity(buffer.Length);
                 ReadOnlySpan<T> span = buffer.ReadOnlySpan;
                 for (int i = 0; i < span.Length; i++)
                 {
@@ -714,9 +706,8 @@ internal PrimitiveColumnContainer<long> CloneAsLongContainer()
             foreach (ReadOnlyDataFrameBuffer<T> buffer in Buffers)
             {
                 ret.Length += buffer.Length;
-                DataFrameBuffer<long> newBuffer = new DataFrameBuffer<long>();
+                DataFrameBuffer<long> newBuffer = new DataFrameBuffer<long>(buffer.Length);
                 ret.Buffers.Add(newBuffer);
-                newBuffer.EnsureCapacity(buffer.Length);
                 ReadOnlySpan<T> span = buffer.ReadOnlySpan;
                 for (int i = 0; i < span.Length; i++)
                 {
@@ -734,9 +725,8 @@ internal PrimitiveColumnContainer<ulong> CloneAsULongContainer()
             foreach (ReadOnlyDataFrameBuffer<T> buffer in Buffers)
             {
                 ret.Length += buffer.Length;
-                DataFrameBuffer<ulong> newBuffer = new DataFrameBuffer<ulong>();
+                DataFrameBuffer<ulong> newBuffer = new DataFrameBuffer<ulong>(buffer.Length);
                 ret.Buffers.Add(newBuffer);
-                newBuffer.EnsureCapacity(buffer.Length);
                 ReadOnlySpan<T> span = buffer.ReadOnlySpan;
                 for (int i = 0; i < span.Length; i++)
                 {
@@ -754,9 +744,8 @@ internal PrimitiveColumnContainer<float> CloneAsFloatContainer()
             foreach (ReadOnlyDataFrameBuffer<T> buffer in Buffers)
             {
                 ret.Length += buffer.Length;
-                DataFrameBuffer<float> newBuffer = new DataFrameBuffer<float>();
+                DataFrameBuffer<float> newBuffer = new DataFrameBuffer<float>(buffer.Length);
                 ret.Buffers.Add(newBuffer);
-                newBuffer.EnsureCapacity(buffer.Length);
                 ReadOnlySpan<T> span = buffer.ReadOnlySpan;
                 for (int i = 0; i < span.Length; i++)
                 {

From 6abf02e2394b893230888ddd829e47407f56d218 Mon Sep 17 00:00:00 2001
From: Aleksei Smirnov <tlalok@inbox.ru>
Date: Sat, 9 Sep 2023 09:08:51 +0300
Subject: [PATCH 5/8] remove uncorrectly added using

---
 src/Microsoft.Data.Analysis/DataFrameBuffer.cs | 1 -
 1 file changed, 1 deletion(-)

diff --git a/src/Microsoft.Data.Analysis/DataFrameBuffer.cs b/src/Microsoft.Data.Analysis/DataFrameBuffer.cs
index c0f2af2f4c..0f73eadf48 100644
--- a/src/Microsoft.Data.Analysis/DataFrameBuffer.cs
+++ b/src/Microsoft.Data.Analysis/DataFrameBuffer.cs
@@ -5,7 +5,6 @@
 using System;
 using System.Runtime.CompilerServices;
 using System.Runtime.InteropServices;
-using Microsoft.ML.Data;
 
 namespace Microsoft.Data.Analysis
 {

From 1a47ce44fd1a0504e82c18e4d51ab137e6ba6c68 Mon Sep 17 00:00:00 2001
From: Aleksei Smirnov <tlalok@inbox.ru>
Date: Sun, 10 Sep 2023 10:20:13 +0300
Subject: [PATCH 6/8] Make DataFrameBuffer Length field protected

---
 .../ArrowStringDataFrameColumn.cs                |  6 +++---
 src/Microsoft.Data.Analysis/DataFrameBuffer.cs   | 16 ++++++++++++----
 .../PrimitiveColumnContainer.cs                  | 14 +++++---------
 .../ReadOnlyDataFrameBuffer.cs                   | 11 ++++++-----
 4 files changed, 26 insertions(+), 21 deletions(-)

diff --git a/src/Microsoft.Data.Analysis/ArrowStringDataFrameColumn.cs b/src/Microsoft.Data.Analysis/ArrowStringDataFrameColumn.cs
index 56041711e3..d0b9479e17 100644
--- a/src/Microsoft.Data.Analysis/ArrowStringDataFrameColumn.cs
+++ b/src/Microsoft.Data.Analysis/ArrowStringDataFrameColumn.cs
@@ -213,9 +213,9 @@ private void Append(ReadOnlySpan<byte> value)
                     _offsetsBuffers.Add(mutableOffsetsBuffer);
                     mutableOffsetsBuffer.Append(0);
                 }
-                mutableDataBuffer.EnsureCapacity(value.Length);
-                value.CopyTo(mutableDataBuffer.RawSpan.Slice(mutableDataBuffer.Length));
-                mutableDataBuffer.Length += value.Length;
+                var startIndex = mutableDataBuffer.Length;
+                mutableDataBuffer.IncreaseSize(value.Length);
+                value.CopyTo(mutableDataBuffer.RawSpan.Slice(startIndex));
                 mutableOffsetsBuffer.Append(mutableOffsetsBuffer[mutableOffsetsBuffer.Length - 1] + value.Length);
             }
             SetValidityBit(Length - 1, value != default);
diff --git a/src/Microsoft.Data.Analysis/DataFrameBuffer.cs b/src/Microsoft.Data.Analysis/DataFrameBuffer.cs
index 0f73eadf48..7aee0a552e 100644
--- a/src/Microsoft.Data.Analysis/DataFrameBuffer.cs
+++ b/src/Microsoft.Data.Analysis/DataFrameBuffer.cs
@@ -15,6 +15,8 @@ namespace Microsoft.Data.Analysis
     internal class DataFrameBuffer<T> : ReadOnlyDataFrameBuffer<T>
         where T : unmanaged
     {
+        private const int MinCapacity = 8;
+
         private Memory<byte> _memory;
 
         public override ReadOnlyMemory<byte> ReadOnlyBuffer => _memory;
@@ -36,14 +38,14 @@ public Span<T> RawSpan
             get => MemoryMarshal.Cast<byte, T>(Buffer.Span);
         }
 
-        public DataFrameBuffer(int numberOfValues = 8)
+        public DataFrameBuffer(int capacity = 0)
         {
-            if ((long)numberOfValues * Size > MaxCapacity)
+            if ((long)capacity * Size > MaxCapacity)
             {
-                throw new ArgumentException($"{numberOfValues} exceeds buffer capacity", nameof(numberOfValues));
+                throw new ArgumentException($"{capacity} exceeds buffer capacity", nameof(capacity));
             }
 
-            _memory = new byte[numberOfValues];
+            _memory = new byte[Math.Max(capacity, MinCapacity)];
         }
 
         internal DataFrameBuffer(ReadOnlyMemory<byte> buffer, int length)
@@ -65,6 +67,12 @@ public void Append(T value)
             Span[Length - 1] = value;
         }
 
+        public void IncreaseSize(int numberOfValues)
+        {
+            EnsureCapacity(numberOfValues);
+            Length += numberOfValues;
+        }
+
         public void EnsureCapacity(int numberOfValues)
         {
             long newLength = Length + (long)numberOfValues;
diff --git a/src/Microsoft.Data.Analysis/PrimitiveColumnContainer.cs b/src/Microsoft.Data.Analysis/PrimitiveColumnContainer.cs
index 78d58bbca5..8c9700fb0e 100644
--- a/src/Microsoft.Data.Analysis/PrimitiveColumnContainer.cs
+++ b/src/Microsoft.Data.Analysis/PrimitiveColumnContainer.cs
@@ -67,9 +67,8 @@ public PrimitiveColumnContainer(ReadOnlyMemory<byte> buffer, ReadOnlyMemory<byte
             ReadOnlyDataFrameBuffer<T> dataBuffer;
             if (buffer.IsEmpty)
             {
-                DataFrameBuffer<T> mutableBuffer = new DataFrameBuffer<T>();
-                mutableBuffer.EnsureCapacity(length);
-                mutableBuffer.Length = length;
+                DataFrameBuffer<T> mutableBuffer = new DataFrameBuffer<T>(length);
+                mutableBuffer.IncreaseSize(length);
                 mutableBuffer.RawSpan.Fill(default(T));
                 dataBuffer = mutableBuffer;
             }
@@ -172,15 +171,12 @@ public void AppendMany(T? value, long count)
 
                 //Calculate how many values we can additionaly allocate and not exceed the MaxCapacity
                 int allocatable = (int)Math.Min(remaining, ReadOnlyDataFrameBuffer<T>.MaxCapacity - mutableLastBuffer.Length);
-                mutableLastBuffer.EnsureCapacity(allocatable);
+                mutableLastBuffer.IncreaseSize(allocatable);
 
                 DataFrameBuffer<byte> lastNullBitMapBuffer = NullBitMapBuffers.GetOrCreateMutable(NullBitMapBuffers.Count - 1);
                 int nullBufferAllocatable = (allocatable + 7) / 8;
-                lastNullBitMapBuffer.EnsureCapacity(nullBufferAllocatable);
+                lastNullBitMapBuffer.IncreaseSize(nullBufferAllocatable);
 
-
-                mutableLastBuffer.Length += allocatable;
-                lastNullBitMapBuffer.Length += nullBufferAllocatable;
                 Length += allocatable;
 
                 if (value.HasValue)
@@ -529,6 +525,7 @@ internal PrimitiveColumnContainer<bool> CloneAsBoolContainer()
             {
                 DataFrameBuffer<bool> newBuffer = new DataFrameBuffer<bool>(buffer.Length);
                 ret.Buffers.Add(newBuffer);
+                newBuffer.IncreaseSize(buffer.Length);
 
                 if (typeof(T) == typeof(bool))
                 {
@@ -540,7 +537,6 @@ internal PrimitiveColumnContainer<bool> CloneAsBoolContainer()
                 {
                     newBuffer.Span.Fill(false);
                 }
-                newBuffer.Length = buffer.Length;
                 ret.Length += buffer.Length;
             }
             ret.NullBitMapBuffers = CloneNullBitMapBuffers();
diff --git a/src/Microsoft.Data.Analysis/ReadOnlyDataFrameBuffer.cs b/src/Microsoft.Data.Analysis/ReadOnlyDataFrameBuffer.cs
index a6a41089e7..069aa3e94a 100644
--- a/src/Microsoft.Data.Analysis/ReadOnlyDataFrameBuffer.cs
+++ b/src/Microsoft.Data.Analysis/ReadOnlyDataFrameBuffer.cs
@@ -48,15 +48,16 @@ public ReadOnlySpan<T> ReadOnlySpan
             get => (MemoryMarshal.Cast<byte, T>(ReadOnlyBuffer.Span)).Slice(0, Length);
         }
 
-        public int Length { get; internal set; }
+        public int Length { get; protected set; }
 
-        public ReadOnlyDataFrameBuffer(int numberOfValues = 8)
+        public ReadOnlyDataFrameBuffer(int length = 0)
         {
-            if ((long)numberOfValues * Size > MaxCapacity)
+            if ((long)length * Size > MaxCapacity)
             {
-                throw new ArgumentException($"{numberOfValues} exceeds buffer capacity", nameof(numberOfValues));
+                throw new ArgumentException($"{length} exceeds buffer capacity", nameof(length));
             }
-            _readOnlyBuffer = new byte[numberOfValues * Size];
+            _readOnlyBuffer = new byte[length * Size];
+            Length = length;
         }
 
         public ReadOnlyDataFrameBuffer(ReadOnlyMemory<byte> buffer, int length)

From be47f8daaf21f2de613b3ab4818521e2ddd741a6 Mon Sep 17 00:00:00 2001
From: Aleksei Smirnov <tlalok@inbox.ru>
Date: Tue, 19 Sep 2023 12:07:23 +0300
Subject: [PATCH 7/8] Fix typo

---
 test/Microsoft.ML.Fairlearn.Tests/GridSearchTest.cs | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/test/Microsoft.ML.Fairlearn.Tests/GridSearchTest.cs b/test/Microsoft.ML.Fairlearn.Tests/GridSearchTest.cs
index e539c10907..35994e6a44 100644
--- a/test/Microsoft.ML.Fairlearn.Tests/GridSearchTest.cs
+++ b/test/Microsoft.ML.Fairlearn.Tests/GridSearchTest.cs
@@ -45,7 +45,7 @@ private DataFrame CreateDummyDataset()
         }
 
         // Data generated so it is identical from Binary_Classification.ipynb from Fairlearn.github on Github
-        private DataFrame CreateGridScearhDataset()
+        private DataFrame CreateGridSearchDataset()
         {
             float[] score_feature = new float[52];
             int index = 0;
@@ -89,7 +89,7 @@ public void TestGridSearchTrialRunner2()
                 }
             };
             var experiment = context.Auto().CreateExperiment();
-            var df = CreateGridScearhDataset();
+            var df = CreateGridSearchDataset();
             var shuffledDataset = context.Data.ShuffleRows(df);
             var trainTestSplit = context.Data.TrainTestSplit(shuffledDataset, 0.2);
             var pipeline = context.Transforms.Categorical.OneHotHashEncoding("sensitiveFeature_encode", "sensitiveFeature")

From d1b06865040a3c68672d3caca42b11e988ac1ecb Mon Sep 17 00:00:00 2001
From: Aleksei Smirnov <tlalok@inbox.ru>
Date: Tue, 19 Sep 2023 13:03:51 +0300
Subject: [PATCH 8/8] Use RawSpan

---
 src/Microsoft.Data.Analysis/DataFrameBuffer.cs | 10 +++-------
 1 file changed, 3 insertions(+), 7 deletions(-)

diff --git a/src/Microsoft.Data.Analysis/DataFrameBuffer.cs b/src/Microsoft.Data.Analysis/DataFrameBuffer.cs
index 7aee0a552e..fd7f23964f 100644
--- a/src/Microsoft.Data.Analysis/DataFrameBuffer.cs
+++ b/src/Microsoft.Data.Analysis/DataFrameBuffer.cs
@@ -57,14 +57,10 @@ internal DataFrameBuffer(ReadOnlyMemory<byte> buffer, int length)
 
         public void Append(T value)
         {
-            if (Length == MaxCapacity)
-            {
-                throw new ArgumentException("Current buffer is full", nameof(value));
-            }
             EnsureCapacity(1);
-            if (Length < MaxCapacity)
-                ++Length;
-            Span[Length - 1] = value;
+
+            RawSpan[Length] = value;
+            Length++;
         }
 
         public void IncreaseSize(int numberOfValues)