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    <p>First, you are assuming the <code>TStream</code> is the bottleneck. You need to profile your code, such as with AQTime, to determine where the bottleneck really is. Don't make assumptions.</p> <p>Second, what type of <code>TStream</code> are you actually using? <code>TMemoryStream</code>? <code>TFileStream</code>? Something else? Different stream types handle memory differently. TMemoryStream allocates a memory buffer and grows it by a pre-set amount of bytes whenever the buffer fills up. <code>TFileStream</code>, on the other hand, doesn't use any memory at all, it just writes directly to the file and lets the OS handle any buffering.</p> <p>Regardless of which type of stream you use, one thing you could try is implement your own custom <code>TStream</code> class that has an internal fixed-size buffer and a pointer to your real destination <code>TStream</code> object. You can then pass an instance of your custom class to your algorithm. Have your class override the <code>TStream::Write()</code> method to copy the input data into its buffer until it fills up, then you can <code>Write()</code> the buffer to the destination <code>TStream</code> and clear the buffer. Your algorithm will never know the difference. Both <code>TMemoryStream</code> and <code>TFileStream</code> would benefit from the extra buffering - fewer larger writes means more efficient memory allocations and file I/O. For example:</p> <pre><code>type TMyBufferedStreamWriter = class(TStream) private fDest: TStream; fBuffer: array[0..4095] of Byte; fOffset: Cardinal; public constructor Create(ADest: TStream); function Read(var Buffer; Count: Longint): Longint; override; function Write(const Buffer; Count: Longint): Longint; override; procedure FlushBuffer; end; </code></pre> <p>.</p> <pre><code>uses RTLConsts; constructor TMyBufferedStreamWriter.Create(ADest: TStream); begin fDest := ADest; end; function TMyBufferedStreamWriter.Read(var Buffer; Count: Longint): Longint; begin Result := 0; end; function TMyBufferedStreamWriter.Write(const Buffer; Count: Longint): Longint; var pBuffer: PByte; Num: Cardinal; begin Result := 0; pBuffer := PByte(@Buffer); while Count &gt; 0 do begin Num := Min(SizeOf(fBuffer) - fOffset, Cardinal(Count)); if Num = 0 then FlushBuffer; Move(pBuffer^, fBuffer[fOffset], Num); Inc(fOffset, Num); Inc(pBuffer, Num); Dec(Count, Num); Inc(Result, Num); end; end; procedure TMyBufferedStreamWriter.FlushBuffer; var Idx: Cardinal; Written: Longint; begin if fOffset = 0 then Exit; Idx := 0; repeat Written := fDest.Write(fBuffer[Idx], fOffset - Idx); if Written &lt; 1 then raise EWriteError.CreateRes(@SWriteError); Inc(Idx, Written); until Idx = fOffset; fOffset := 0; end; </code></pre> <p>.</p> <pre><code>Writer := TMyBufferedStreamWriter.Create(RealStreamHere); try ... write data to Writer normally as needed... Writer.FlushBuffer; finally Writer.Free; end; </code></pre>
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