Hello Nathan,
Thanks for your response. I first noticed the memory leak in a larger
application I was working on written in C++. I then realized that the leak
can be reproduced in every programming language I tried with a minimal
amount of code. I've included examples in VB, C++, and Delphi below. It all
seems to center around the "Connect" or "ConnectServer" call if the username
and password is not blank. The amount of the memory leak is always the same
at around 4Kb per connection.
If the computer running this code is on a domain and can log into the remote
computer using default security (without specifying username and password),
then there is no memory leak even if the username and password is specified.
If not, the memory consumption continues to climb until it either crashes
with an 'access violation' or it simply disappears with the following alert
message.
************************************************** *
Windows - Virtual Memory Minimum too low
Your system is low on virtual memory. Windows is
increasing the size of your virtual memory paging
file. During this process, memory requests for
some applications may be denied. For more information,
see help.
************************************************** *
Thanks again for your help.
Don
'************************************************* *********
'VB Example
'************************************************* *********
Do
Set locator = CreateObject("wbemscripting.swbemlocator")
Set oWMI = locator.connectserver("wimc0964", "root/cimv2", "administrator",
"system2")
locator = Null
oWMI = Null
Loop
//************************************************** *********
C++ Example */
//************************************************** ********
while(1==1)
{
CoInitializeEx(0, COINIT_APARTMENTTHREADED) ;
CoInitializeSecurity
(
NULL, -1, NULL, NULL,
RPC_C_AUTHN_LEVEL_DEFAULT,
RPC_C_IMP_LEVEL_IMPERSONATE,
NULL, EOAC_NONE, 0
) ;
ISWbemLocator *t_Locator = NULL ;
HRESULT t_Result = CoCreateInstance (
CLSID_SWbemLocator ,
NULL ,
CLSCTX_INPROC_SERVER | CLSCTX_LOCAL_SERVER ,
IID_ISWbemLocator,
( void ** ) & t_Locator
) ;
ISWbemServices *t_Service = NULL ;
t_Result = t_Locator->ConnectServer (
L"computername" ,
L"root\\cimv2",
L"username" ,
L"password" ,
NULL ,
0 ,
NULL,
NULL,
&t_Service
) ;
t_Service->Release () ;
t_Locator->Release () ;
CoUninitialize();
}
//************************************************** *********
//Delphi Example - Call Make Connection in a loop
//************************************************** *********
unit WmiDelphiTest;
interface
uses Wbemads;
procedure MakeConnection ();
implementation
procedure MakeConnection ();
var
WbemLocator: ISWbemLocator;
pService: ISWbemServices;
begin
WbemLocator := CoSWbemLocator.create;
pService := WbemLocator.ConnectServer('MachineName', 'root\cimv2',
'UserName', 'Password', '', '', 0, pService);
end;
end.
"Nathan Neitzke" <ne******@erau.edu> wrote in message
news:%2****************@TK2MSFTNGP12.phx.gbl...
It is really hard to tell from that small of a code snippet. But you have
an endless loop there, right? Well, in that case you are creating
infinite ManagementScope objects theoretically. Practically, when the garbage
collector is run will be the only time objects are cleaned up. So it
would make sense that if you continually instantiate new objects that your app
would increase in memory size?
Like I said, there is probably more to the picture here, I just don't get
it from the code snippet you provided.
Lastly, as far as when it crashes - what kind of exception do you get when
it does crash?
Take care.
--
Nathan
"Don Nell" <do*****@nospam.com> wrote in message
news:KbNZd.136400$tl3.101953@attbi_s02... Hello
Why is there a memory leak when this code is executed.
for(;;)
{
ManagementScope scope = new ManagementScope();
scope.Options.Username="username";
scope.Options.Password="password";
scope.Path.Path=@"\\pc\root\cimv2";
scope.Connect();
}
There is no leak if the username and password is blank and the computer
is in a domain. At first I thought it had something to do with Windows'
inablility to release more than 9 security context entries per 10
seconds (see link below), but the leak still exist when I slow it down.
http://support.microsoft.com/default...b;en-us;890196
I also tried calling RpcMgmtEnableIdleCleanup() at startup and also
forcing
any unused memory back to the operating system with
SetProcessWorkingSetSize
but nothing helps. The Windows task manger always shows my application
consuming more and more memory until it finally crashes.
Thanks.
Don
