public void Swap(UnmanagedSliceBuilder other)
{
if (other == null)
{
throw new ArgumentNullException("other");
}
if (m_buffer == null || other.m_buffer == null)
{
ThrowAlreadyDisposed();
}
try
{ }
finally
{
var handle = other.m_handle;
var buffer = other.m_buffer;
var data = other.m_data;
var sz = other.m_count;
other.m_handle = m_handle;
other.m_buffer = buffer;
other.m_data = m_data;
other.m_count = m_count;
m_handle = handle;
m_buffer = buffer;
m_data = data;
m_count = sz;
}
}
/// <summary>Borrow a builder from this pool</summary>
/// <returns>Builder subscription that should be disposed as soon as the buffer is not needed anymore</returns>
/// <remarks>ALWAYS wrap the subscription in a using(...) statement! Do NOT pass the subscription by value, always pass the Builder by reference ! Do NOT keep a reference on the Builder or reuse it after it has been disposed! Do NOT return or store slices that point to this buffer! </remarks>
public Subscription Use()
{
UnmanagedSliceBuilder builder = null;
lock (m_buckets)
{
if (m_disposed)
{
ThrowDisposed();
}
while (m_buckets.Count > 0)
{
builder = m_buckets.Pop();
if (builder != null && builder.Buffer != null)
{
Interlocked.Add(ref m_memoryUsed, -((long)builder.Capacity));
Contract.Assert(m_memoryUsed >= 0, "m_memoryUsed desync");
break;
}
builder = null;
}
}
if (builder == null)
{
builder = new UnmanagedSliceBuilder(m_initialCapacity);
}
Interlocked.Add(ref m_memoryLoaned, builder.Capacity);
Contract.Assert(builder != null && builder.Buffer != null);
return(new Subscription(this, builder));
}
/// <summary>Return a builder into the pool</summary>
/// <param name="builder">Builder that is no longer in use</param>
internal void Return(UnmanagedSliceBuilder builder)
{
if (m_disposed || builder == null)
{
return;
}
lock (m_buckets)
{
if (m_disposed)
{
return;
}
var size = builder.Capacity;
Contract.Assert(size == UnmanagedHelpers.NextPowerOfTwo(size), "builder size should always be a power of two");
Interlocked.Add(ref m_memoryLoaned, -((long)builder.Capacity));
Contract.Assert(m_memoryUsed >= 0, "m_memoryLoaned desync");
if (m_buckets.Count < m_maxCount)
{
m_buckets.Push(builder);
Interlocked.Add(ref m_memoryUsed, builder.Capacity);
}
else
{
builder.Dispose();
}
}
}
internal Subscription(UnmanagedSliceBuilderPool pool, UnmanagedSliceBuilder builder)
{
Contract.Requires(pool != null && builder != null);
m_pool = pool;
m_builder = builder;
}
public DebugView(UnmanagedSliceBuilder builder)
{
m_builder = builder;
}
public DebugView(UnmanagedSliceBuilder builder)
{
m_builder = builder;
}
public void Swap(UnmanagedSliceBuilder other)
{
if (other == null) throw new ArgumentNullException("other");
if (m_buffer == null || other.m_buffer == null) ThrowAlreadyDisposed();
try
{ }
finally
{
var handle = other.m_handle;
var buffer = other.m_buffer;
var data = other.m_data;
var sz = other.m_count;
other.m_handle = m_handle;
other.m_buffer = buffer;
other.m_data = m_data;
other.m_count = m_count;
m_handle = handle;
m_buffer = buffer;
m_data = data;
m_count = sz;
}
}
/// <summary>Checks if a list of reads conflicts with at least one write performed in this transaction window</summary>
/// <param name="reads">List of reads to check for conflicts</param>
/// <param name="version">Sequence number of the transaction that performed the reads</param>
/// <returns>True if at least one read is conflicting with a write with a higher sequence number; otherwise, false.</returns>
public bool Conflicts(ColaRangeSet<Slice> reads, ulong version)
{
Contract.Requires(reads != null);
//Debug.WriteLine("* Testing for conflicts for: " + String.Join(", ", reads));
if (version > m_maxVersion)
{ // all the writes are before the reads, so no possible conflict!
//Debug.WriteLine(" > cannot conflict");
return false;
}
using (var scratch = new UnmanagedSliceBuilder())
{
//TODO: do a single-pass version of intersection checking !
foreach (var read in reads)
{
scratch.Clear();
scratch.Append(read.Begin);
var p = scratch.Count;
scratch.Append(read.End);
var begin = scratch.ToUSlice(p);
var end = scratch.ToUSlice(p, scratch.Count - p);
if (m_writeConflicts.Intersect(begin, end, version, (v, min) => v > min))
{
Debug.WriteLine(" > Conflicting read: " + read);
return true;
}
}
}
//Debug.WriteLine(" > No conflicts found");
return false;
}
/// <summary>Borrow a builder from this pool</summary>
/// <returns>Builder subscription that should be disposed as soon as the buffer is not needed anymore</returns>
/// <remarks>ALWAYS wrap the subscription in a using(...) statement! Do NOT pass the subscription by value, always pass the Builder by reference ! Do NOT keep a reference on the Builder or reuse it after it has been disposed! Do NOT return or store slices that point to this buffer! </remarks>
public Subscription Use()
{
UnmanagedSliceBuilder builder = null;
lock (m_buckets)
{
if (m_disposed) ThrowDisposed();
while(m_buckets.Count > 0)
{
builder = m_buckets.Pop();
if (builder != null && builder.Buffer != null)
{
Interlocked.Add(ref m_memoryUsed, -((long)builder.Capacity));
Contract.Assert(m_memoryUsed >= 0, "m_memoryUsed desync");
break;
}
builder = null;
}
}
if (builder == null)
{
builder = new UnmanagedSliceBuilder(m_initialCapacity);
}
Interlocked.Add(ref m_memoryLoaned, builder.Capacity);
Contract.Assert(builder != null && builder.Buffer != null);
return new Subscription(this, builder);
}
internal Subscription(UnmanagedSliceBuilderPool pool, UnmanagedSliceBuilder builder)
{
Contract.Requires(pool != null && builder != null);
m_pool = pool;
m_builder = builder;
}
/// <summary>Return a builder into the pool</summary>
/// <param name="builder">Builder that is no longer in use</param>
internal void Return(UnmanagedSliceBuilder builder)
{
if (m_disposed || builder == null) return;
lock (m_buckets)
{
if (m_disposed) return;
var size = builder.Capacity;
Contract.Assert(size == UnmanagedHelpers.NextPowerOfTwo(size), "builder size should always be a power of two");
Interlocked.Add(ref m_memoryLoaned, -((long)builder.Capacity));
Contract.Assert(m_memoryUsed >= 0, "m_memoryLoaned desync");
if (m_buckets.Count < m_maxCount)
{
m_buckets.Push(builder);
Interlocked.Add(ref m_memoryUsed, builder.Capacity);
}
else
{
builder.Dispose();
}
}
}
