Mastering Delphi Programming:A Complete Reference Guide
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ScaleMM

First such memory manager is ScaleMM. It is the work of André Mussche and can be downloaded from https://github.com/andremussche/scalemm. You can use it in practically any application, as it is released under a tri-license MPL 1.1/GPL 2.0/LGPL 2.1. It only supports the Windows platform.

ScaleMM is written in Delphi and assembler. To use ScaleMM, you just have to download it, store it somewhere on the disk and add the ScaleMM2 unit as a first unit in the program.

ScaleMM was created as a faster replacement for FastMM. It is not as loaded with debugging features as FastMM but implements just a base memory manager functionality. Because of that, it makes sense to run FastMM while debugging, and ScaleMM while testing and in production.

The older version of Delphi didn't like it if you put the {$IFDEF} directive inside the main program's uses list. Delphi will remove this directive when you add a new form to the program. The easiest way to fix this is to create a new unit and add it as a first unit in the main program's uses list. In this new unit, you can then put {$IFDEF} in the used memory manager however you wish.

An example of the uses list in such a main program is shown here:

program ParallelAllocation;

uses
ParallelAllocationMM,
Vcl.Forms,
ParallelAllocationMain in 'ParallelAllocationMain.pas' {frmParallelAllocation};

Unit ParallelAllocationMM can then be implemented as shown here:

unit ParallelAllocationMM;

interface

uses
{$IFDEF DEBUG}
FastMM4 in 'FastMM\FastMM4.pas';
{$ELSE}
ScaleMM2 in 'ScaleMM\ScaleMM2.pas';
{$ENDIF}

implementation

end.

Replacing FastMM with ScaleMM in the test program, ParallelAllocation shows a noticeable improvement. With FastMM and {$DEFINE UseReleaseStack}, the parallel version is at best 6.3x faster than the serial one. With ScaleMM it is up to 6.7x faster: