RTC Forums

I have this code:

class function TServer_Utils.JSONFromDataset(ADataset: TDataSet): String;
var
  rtcDS: TRtcDataSet;
  AHugeString: TRtcHugeString;
begin
  AHugeString := nil;
  rtcDS := TRtcDataSet.Create;
  try
    AHugeString := TRtcHugeString.Create;

    DelphiDataSetToRtc(ADataset, rtcDS); // This function is in the "rtcDB" unit
    rtcDS.to_JSON(AHugeString);
    Result := AHugeString.Get;
  finally
    // rtcDS.Clear;

    FreeAndNil(rtcDS);
    FreeAndNil(AHugeString);
  end;
end;


It is 800 rows in the dataset
It uses 10 mb of memory, but only the first time it is used,

Here is the memory use:
12 MB
  DelphiDataSetToRtc(ADataset, rtcDS);
18 MB
    rtcDS.to_JSON(AHugeString);
21 MB
    Result := AHugeString.Get;
23 MB
  FreeAndNil(rtcDS);
21 MB
    FreeAndNil(AHugeString);
21MB


Shouldn't it be possible to do this without any memory leak?

Jørgen

How are you checking your Application's Memory Usage?

Best Regards,
Danijel Tkalcec

By the way (not directly related to your memory question) ... if you just want a JSON String from a TRtcValueObject instance (like TRtcDataSet), there is no need to manually declare, create and free a local TRtcHugeString variable. You can simply use the "toJSON" method (or "toJSONEx" - if you want a RtcByteArray instead of a String).

In other words, your code example (from above) would look like this:

class function TServer_Utils.JSONFromDataset(ADataset: TDataSet): String;
var
  rtcDS: TRtcDataSet;
begin
  rtcDS := TRtcDataSet.Create;
  try
    DelphiDataSetToRtc(ADataset, rtcDS); // This function is in the "rtcDB" unit
    Result := rtcDS.toJSON;
  finally
    rtcDS.Free;
  end;
end;

Best Regards,
Danijel Tkalcec

Check these DocWiKi Topics about Delphi Memory Management:
http://docwiki.embarcadero.com/RADStudio/XE8/en/Memory_Management
http://docwiki.embarcadero.com/RADStudio/XE8/en/Monitoring_Memory_Usage
http://docwiki.embarcadero.com/RADStudio/XE8/en/Configuring_the_Memory_Manager

Best Regards,
Danijel Tkalcec