How do I force release memory occupied by MemoryStream?

Question

I have the following code:

const int bufferSize = 1024 * 1024;
var buffer = new byte[bufferSize];
for (int i = 0; i < 10; i++)
{
    const int writesCount = 4         


        

Answer 1

Try to force garbage collection when you are sure that it is necessary to clean unreferenced objects.

GC.Collect();
GC.WaitForPendingFinalizers();
GC.Collect();

Another alternative is to use the Stream with external storage: FileStream, for example.

But, in general case, it would be better to use one small enough buffer (array, allocated one time) and use it for read/write calls. Avoid having many large objects in .NET (see CLR Inside Out: Large Object Heap Uncovered).

Update

Assuming that the writesCount is the constant, the why not allocate one buffer and reuse it?

const int bufferSize = 1024 * 1024;
const int writesCount = 400;

byte[] streamBuffer = new byte[writesCount * bufferSize];
byte[] buffer = new byte[bufferSize];
for (int i = 0; i < 10; i++)
{
    using (var stream = new MemoryStream(streamBuffer))
    {
        for (int j = 0; j < writesCount; j++)
        {
            stream.Write(buffer, 0, buffer.Length);
        }
    }
}