Question

我使用echostring和reversestring示例方法在Delphi XE8中使用向导创建了一个简单的DataSnap客户端/服务器应用程序。当我把＆＃34; ReportMemoryLeaksOnShutdown：= True＆＃34;在服务器dpr中，从客户端调用echostring和/或reversestring方法，结果很好但是当我关闭服务器应用程序时（关闭客户端之后），我总是得到2个或更多的未知内存泄漏。这是一个我无法在互联网上找到的已知错误，还是有解决方案？

服务器代码：

unit ServerMethodsUnit;

interface

uses System.SysUtils, System.Classes, System.Json,
Datasnap.DSServer, Datasnap.DSAuth, DataSnap.DSProviderDataModuleAdapter;

type
{$METHODINFO ON}
  TServerMethods = class(TDataModule)
  private
    { Private declarations }
  public
    { Public declarations }
    function EchoString(Value: string): string;
    function ReverseString(Value: string): string;
  end;
{$METHODINFO OFF}

implementation

{%CLASSGROUP 'FMX.Controls.TControl'}

{$R *.dfm}


uses System.StrUtils;

function TServerMethods.EchoString(Value: string): string;
begin
  Result := Value;
end;

function TServerMethods.ReverseString(Value: string): string;
begin
  Result := System.StrUtils.ReverseString(Value);
end;

end.

DFM

object ServerContainer: TServerContainer
  OldCreateOrder = False
  Height = 271
  Width = 415
  object DSServer1: TDSServer
    Left = 96
    Top = 11
  end
  object DSTCPServerTransport1: TDSTCPServerTransport
    Server = DSServer1
    Filters = <>
    Left = 96
    Top = 73
  end
  object DSServerClass1: TDSServerClass
    OnGetClass = DSServerClass1GetClass
    Server = DSServer1
    Left = 200
    Top = 11
  end
end

dfm项目文件

program DataSnap_Server;

uses
  FMX.Forms,
  Web.WebReq,
  IdHTTPWebBrokerBridge,
  ServerMainForm in 'ServerMainForm.pas' {Form2},
  ServerMethodsUnit in 'ServerMethodsUnit.pas' {ServerMethods: TDataModule},
  ServerContainerUnit in 'ServerContainerUnit.pas' {ServerContainer: TDataModule};

{$R *.res}

begin
  ReportMemoryLeaksOnShutdown := True;
  Application.Initialize;
  Application.CreateForm(TForm2, Form2);
  Application.CreateForm(TServerContainer, ServerContainer);
  Application.Run;
end.

客户端代码生成源

// 
// Created by the DataSnap proxy generator.
// 14-5-2015 22:45:56
// 

unit ClientClassesUnit;

interface

uses System.JSON, Data.DBXCommon, Data.DBXClient, Data.DBXDataSnap, Data.DBXJSON, Datasnap.DSProxy, System.Classes, System.SysUtils, Data.DB, Data.SqlExpr, Data.DBXDBReaders, Data.DBXCDSReaders, Data.DBXJSONReflect;

type
  TServerMethodsClient = class(TDSAdminClient)
  private
    FEchoStringCommand: TDBXCommand;
    FReverseStringCommand: TDBXCommand;
  public
    constructor Create(ADBXConnection: TDBXConnection); overload;
    constructor Create(ADBXConnection: TDBXConnection; AInstanceOwner: Boolean); overload;
    destructor Destroy; override;
    function EchoString(Value: string): string;
    function ReverseString(Value: string): string;
  end;

implementation

function TServerMethodsClient.EchoString(Value: string): string;
begin
  if FEchoStringCommand = nil then
  begin
    FEchoStringCommand := FDBXConnection.CreateCommand;
    FEchoStringCommand.CommandType := TDBXCommandTypes.DSServerMethod;
    FEchoStringCommand.Text := 'TServerMethods.EchoString';
    FEchoStringCommand.Prepare;
  end;
  FEchoStringCommand.Parameters[0].Value.SetWideString(Value);
  FEchoStringCommand.ExecuteUpdate;
  Result := FEchoStringCommand.Parameters[1].Value.GetWideString;
end;

function TServerMethodsClient.ReverseString(Value: string): string;
begin
  if FReverseStringCommand = nil then
  begin
    FReverseStringCommand := FDBXConnection.CreateCommand;
    FReverseStringCommand.CommandType := TDBXCommandTypes.DSServerMethod;
    FReverseStringCommand.Text := 'TServerMethods.ReverseString';
    FReverseStringCommand.Prepare;
  end;
  FReverseStringCommand.Parameters[0].Value.SetWideString(Value);
  FReverseStringCommand.ExecuteUpdate;
  Result := FReverseStringCommand.Parameters[1].Value.GetWideString;
end;


constructor TServerMethodsClient.Create(ADBXConnection: TDBXConnection);
begin
  inherited Create(ADBXConnection);
end;


constructor TServerMethodsClient.Create(ADBXConnection: TDBXConnection; AInstanceOwner: Boolean);
begin
  inherited Create(ADBXConnection, AInstanceOwner);
end;


destructor TServerMethodsClient.Destroy;
begin
  FEchoStringCommand.DisposeOf;
  FReverseStringCommand.DisposeOf;
  inherited;
end;

end.

拥有资源

unit ClientMainForm;

interface

uses
  Winapi.Windows, Winapi.Messages, System.SysUtils, System.Variants, System.Classes, Vcl.Graphics,
  Vcl.Controls, Vcl.Forms, Vcl.Dialogs, Vcl.StdCtrls;

type
  TForm1 = class(TForm)
    Button1: TButton;
    Edit1: TEdit;
    Button2: TButton;
    Label1: TLabel;
    procedure Button1Click(Sender: TObject);
    procedure Button2Click(Sender: TObject);
  private
    { Private declarations }
  public
    { Public declarations }
  end;

var
  Form1: TForm1;

implementation

{$R *.dfm}

uses
  ClientModuleUnit;

procedure TForm1.Button1Click(Sender: TObject);
begin
  Label1.Caption := ClientModule.ServerMethodsClient.EchoString(Edit1.Text);
end;

procedure TForm1.Button2Click(Sender: TObject);
begin
  Label1.Caption := ClientModule.ServerMethodsClient.ReverseString(Edit1.Text);
end;

end.

Answer 1

内存泄漏看起来总是存在，或者，我们做错了。

我检查了什么：

我将所有服务器应用程序代码移动到一个单元中。我尝试没有FMX的服务器应用程序 - 使用VCL。我尝试在父亲Self和Nil的运行时创建TDSServer，TDSTCPServerTransport，TDSServerClass。我尝试使用TServerMethod类所有者TPersistance和TComponent（Delphi帮助说要使用它）。我在Delphi XE7 Update 1和Delphi XE8中尝试使用已编译的服务器应用程序作为32位和64位应用程序。

EurekaLog 7.2.2也无法捕获有关内存泄漏的详细信息。为避免捕获EurekaLog的访问冲突，需要在退出前使用DSServer1.Stop。

我们在使用EurekaLog时会发现访问冲突基本上它在 System.TObject.InheritsFrom（???） System._IsClass（$ 64AE4E0，TDSServerTransport） Datasnap.DSCommonServer.TDSCustomServer.StopTransports Datasnap.DSCommonServer.TDSCustomServer.Stop Datasnap.DSServer.TDSServer.Stop Datasnap.DSServer.TDSServer.Destroy System.TObject.Free System.Classes.TComponent.DestroyComponents System.Classes.TComponent.Destroy System.Classes.TDataModule.Destroy System.TObject.Free System.Classes.TComponent.DestroyComponents FMX.Forms.DoneApplication System.SysUtils.DoExitProc System._Halt0 ：00408da8 TObject.InheritsFrom + $ 8

服务器应用：

unit ufmMain;

interface

uses
  Winapi.Windows, Winapi.Messages, System.SysUtils, System.Variants, System.Classes, Vcl.Graphics,
  Vcl.Controls, Vcl.Forms, Vcl.Dialogs,
  Datasnap.DSServer, Datasnap.DSTCPServerTransport, Datasnap.DSAuth, DataSnap.DSProviderDataModuleAdapter, Datasnap.DSCommonServer,
  IPPeerServer;

type
{$METHODINFO ON}
  TServerMethods = class(TComponent)
  private
    { Private declarations }
  public
    { Public declarations }
    function EchoString(Value: string): string;
  end;
{$METHODINFO OFF}


  TfmMain = class(TForm)
    procedure FormCreate(Sender: TObject);
    procedure FormDestroy(Sender: TObject);
  private
    { Private declarations }
  public
    { Public declarations }
    DSServer1: TDSServer;
    DSTCPServerTransport1: TDSTCPServerTransport;
    DSServerClass1: TDSServerClass;
    procedure DSServerClass1GetClass(DSServerClass: TDSServerClass; var PersistentClass: TPersistentClass);
  end;

var
  fmMain: TfmMain;

implementation

{$R *.dfm}

uses System.StrUtils;

function TServerMethods.EchoString(Value: string): string;
begin
  Result := Value;
end;

procedure TfmMain.DSServerClass1GetClass(DSServerClass: TDSServerClass; var PersistentClass: TPersistentClass);
begin
  PersistentClass := TServerMethods;
end;

procedure TfmMain.FormCreate(Sender: TObject);
begin
  DSServer1 := TDSServer.Create(nil);
  DSServer1.Name := 'DSServer1';
  DSServer1.AutoStart := False;

  DSTCPServerTransport1 := TDSTCPServerTransport.Create(nil);
  DSTCPServerTransport1.Server := DSServer1;

  DSServerClass1 := TDSServerClass.Create(nil);
  DSServerClass1.Server := DSServer1;
  DSServerClass1.OnGetClass := DSServerClass1GetClass;

  DSServer1.Start;
end;

procedure TfmMain.FormDestroy(Sender: TObject);
begin
  DSServer1.Stop;

  DSServerClass1.Free;
  DSTCPServerTransport1.Free;
  DSServer1.Free;
end;

end.

Answer 2

我想这是XE8的一个已知错误，我认为它非常严重，至少对我们来说不够严重，以至于在Embarcadero给我们答案之前不要使用XE8 。我们在XE2中遇到了类似的问题，据我记得它是在大量回调中。

这个Eurekalog并没有告诉我多少，它看起来像是深入的数据库，对不起我不知道如何使日志更具可读性。

编辑：我向Embarcadero报告了这个问题，今天得到了回应：

// 嗨亨里克，

部分内存泄漏是由于System.Collections.Generics.pas中的一个错误引起的，我们正在考虑在不久的将来发布修复此问题。

brgds

罗伊。 //

以为你可能想知道：）

简单的DataSnap客户端和服务器应用程序中的Delphi XE8未知内存泄漏

2 个答案: