Delphi: How to organize source code to increase compiler performance

compiler-constructiondelphioptimization

I'm working on a large delphi 6 project with quite a lot of dependancies. It takes several minutes to compile the whole project. The recompilation after a few changes is sometimes much more longer so that it is quicker to terminate Delphi, erase all dcu files and recompile everything.

Does anyone know a way to identify, what makes the compiler slower and slower? Any tips how to organize the code to improve compiler performance?

I have already tried following things:

Explicitly include most of the units in the dpr instead of relying on the search path: It didn't improve anything.
Use the command line compiler dcc32: it isn't faster.
Try to see what the compiler does (using ProcessExplorer from SysInternals): apparently it runs most of the time a function called 'KibitzGetOverloads'. But I can't do anything with this information…

EDIT, Summary of the answers until now:

The answer that worked best in my case:

The function "Clean unused units references" from cnpack. It almost automatically cleaned more than 1000 references, making a "cold" compilation about twice faster. ("cold" compilation = erase all dcu files before compiling). It gets the reference list from the compiler. So if you have some {$IFDEF } check that all your configurations still compile.

The next thing I would like to try:

Refactoring the unit references manually (eventually using an abstract class)
but it is much more work, since I first need to identify where the problems are. Some tools that might help:
- GExperts adds a project dependencies browser to the delphi IDE (but unfortunately it can not show the size of each branch)
- Delphi Unit Dependency Viewer V1.0 do about the same thing but without Delphi. It can calculate some simple statistics (Which units is the most referenced, …)
- Icarus which is referenced on a link in one of the answer.

Things that didn't change anything in my case:

Putting every files from my program and all components in one folder without subfolders.
Defragmenting the disk (I tried with a ramdisk)
Using a ramdisk for the code source and output folders.
Turning off the live scanning antivirus
Listing all the units in the dpr file instead of relying on the search path.
Using the command line compiler dcc32 or ecc32.

Things that didn't apply to my case:

Avoiding having dependencies on network shares.
Using DelphiSpeedUp, because I already had it.
Using a single folder for all dcu (I always do it)

Things that I didn't try:

Upgrading to another Delphi version.
Using dcc32speed.exe
Using a solid-state drive (I didn't tried it, but I tried with a ramdisk where I put all the source code. But maybe I should have installed delphi on the ramdisk too)

Best Answer

Some things that could slow down the compiler

Redundant units in your uses clause. See this question for a link to CnPack.
Not explicitly adding units to your project file. You've already seem to have covered that.
Changed compiler settings, most notably include TDD32 info.

Try to get rid of unused units in your uses clause and see if it makes a difference.

Related Solutions

Delphi: How to use all units and unit references of one project in another project

The way I would go about implementing this would be to create a program to take an existing DPR file and generate a include file that I would then use in my testing application. You can probably do most of this using a tStringlist. This project would be run PRIOR to building your test cases.

var
  OrigDpr : tStringlist;
begin
  OrigDpr := tSTringlist.create;
  OrigDpr.LoadFromFile( originalprojectname );
  while (OrigDpr.Count > 0) and (not SameText('uses',OrigDpr.Strings[0])) do
    OrigDpr.Delete(0);
  // delete the uses line.
  if (OrigDpr.Count > 0) then
    OrigDpr.Delete(0);
  while (OrigDpr.Count > 0) and 
        (not SameText('{$R *.RES}',OrigDpr.Strings[OrigDpr.Count-1]) do
    OrigDpr.Delete(OrigDpr.Count-1);
  // delete the $R reference
  if (OrigDpr.Count > 0) then
    OrigDpr.Delete(OrigDpr.Count-1);

  OrigDpr.SaveToFile( 'pathtotestproject\TESTPROJECT.INC' );
end;

Then in your test DPR, add the following code in your project uses clause. Since the uses clause include file already includes the semicolon, use the include file at the end of your normal test units.:

USES
  // test units go FIRST
  {$I pathtotestproject\TESTPROJECT.INC}

My assumption is that you are performing late/loose binding, which is why all of this is necessary in the first place (the units are not referenced other than being in the DPR). Otherwise just using any of the units would be sufficient enough to have the initialization code executed.

EDIT

Another option would be to have the first program generate a complete unit, and then use this unit in your test application. This will compile in the initialization/finalization code from all of the referenced units. Your test application then would have to use the global repository you mentioned to gain access to these objects.

An important piece here is to make sure that the test project search path includes the source directories for the other project.

Delphi – How to correctly set “Directories/Conditionals” and “Library” path

You should explicitely compile packages - just compiling package files is not enough and as you have noticed leads to problems. In modern Delphi versions you can create a project group (not sure about Delphi 7) that contains an application and packages you want to develop with the application, and you can easily switch between them and complile packages without need to close/reopen the application.
BlgPackage should not have an access to MyControls package sources (through "Library" path or by using the same directory), it should access only already compiled MyControls package, else the files from MyControls are compiled every time you build BlgPackage and the compiled files are stored in BlgControls DCU directory

ADDED

The "Library" path should lead to compiled files (.dcp, .dcu) and (if needed) resource files (.res, .dfm) only - it is enough to compile applications and packages that requires "MyControls" package. You can set the directory for compiled files directly in the package settings, and you should copy the resource files (if you need them) to the same directory manually. This directory should be included into "Library" path, or else you can use a directory already contained in "Library" path.

The "Library" path should not lead to source files (.pas) if you don't want these files to be compiled every time you build your BlgPackage or an application that requires "MyControls" package.

Best Answer

Related Solutions

Delphi: How to use all units and unit references of one project in another project

Delphi – How to correctly set “Directories/Conditionals” and “Library” path

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