What Simple Changes Made the Biggest Improvements to Your Delphi Programs [closed]

Answer 1

Check heavily-used loops for calculations that could be (at least partially) pre-calculated or handled with a lookup table. Trig functions are a classic for this, but it applies to many others.

Answer 2

Examine all loops, and look for ways to short circuit. If your looking for something specific and find it in a loop, then use the BREAK command to immediately bail...no sense looping thru the rest. If you know that you don't have a match, then use a CONTINUE as quickly as possible.

Answer 3

Consider the careful use of threads. If you are not using threads now, then consider adding a couple. If you are, make sure you are not using too many. If you are running on a Dual or Quad core computer (which most are any more) then proper thread tuning is very important.

You could look at OmniThread Library by Gabr, but there are a number of thread libraries in development for Delphi. You could easily implement your own parallel for using anonymous types.

Answer 4

Make intelligent use of SetLength() for strings and arrays. Optimise initialisation with FillChar or ZeroMemory.

Local variables created on stack (e.g. record types) are faster than heap allocated (objects and New()) variables.

Reuse objects rather than Destroy then create. But make sure management code for this is faster than memory manager!

Answer 5

1. Create unit tests
2. Verify tests all pass
3. Profile your application
4. Refactor looking for bottlenecks and memory
5. Repeat from Step 2 (comparing to previous pass)

Answer 6

Separating the program logic from user interface, refactoring, then optimizing the most-used, most resource-intensive elements independently.