record-pool-delphi

Dynamic Record Pool with Stable Pointers (Delphi)

Code for blog post https://schellingerhout.github.io/memory%20management/record-pool-delphi/

New as defined in System.pas can be slow in repeated calls to create records, to speed it up we can use a Pool to allocate new records and return pointers. For instance:

Given these types

type
PMyRec = ^TMyRec;
TMyRec = Record
// ... details of record immaterial
end;

Declare a pool as follows

var
  RecordPool: TPool<TMyRec>;

And use New on the pool instead to get a pointer instead of the System.New() loose function

var
  RecordPtr: PMyRec;
begin
...
   RecordPtr := RecordPool.New();
...
end;

As applications require please modify AddARow as needed, to potentially grow rows (e.g. 1.5 times the size of the prior row). Alternatively extend this type to accept a custom growth function to determine pool growth.