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Out of timers

Hi,

My application uses a lot of timers while running.
After a few days of running, it is unable to create timers., i.e.
it is unable to execute "TTimer.Create", probably because of lack of system resources.
Even when I restart my application it still happens, and only when I reboot the computer I can continue working.

I work on windows NT 4.0 service pack 3 and Delphi 3.
I am pretty sure that I do free every timer I use, and I am suspecting that the NT has a limit for using timers.
I have checked for memory and resource leaks using TurboPower's Memory Sleuth, and there were no leaks.

Thanks,
Ori.

Motaz

Make sure that you assign nil to Timer.OnTimer

Motaz

God_Ares

How many timers are you using at once?

for what purpose?

TheNeil

There IS a limit on th number of timers that Windows can support simultaneously (can't remember what it is but 8 seems to be familair). Have you thought about using threads?

The Neil =:(

shenqw

you must release the timer when you don't need it.

I think you don't need so many timer.you can do it like this

var
aTimeCounter:array of [0..255] of integer;
aTimeLimit:array of [0..255] of integer;

procedure TForm1.Timer1Timer(Sender: TObject);
var
i:integer;
begin
for i:=0 to 255 do
begin
Inc(aTimeCounter[i]);
if aTimeCounter[i]>aTimerLimit then
begin
//PostMessage or SendMessage
aTimeCounter[i]:=0;
end;
end;
end;

msedi

Hello,

you said you are sure you free a the timers. In order to check if that's right. Put a counter for created and a counter for freed timers. If there's a difference you know it definitely.

In order to free the timer use FreeAndNil("Timer") in order to force the Timer to be removed from the memory.

Good luck, Martin

mullet_attack

Hey msedit, thanks for the 'freeandnil' proc !

I've been using Delphi for 5 years, and I have never seen it !

Thanks, you can always learn...

Epsylon

FreeAndNil is new in Delphi 5....

oris

ASKER

Adjusted points from 250 to 300

oris

ASKER

msedi:
I did try putting counters and the results were (num of creates) - (num of frees) = 0.
I use Delphi 3, so I don't have the ability to use "FreeAndNil".

I suspect that NT has an absolute limit for using timers during an NT session.

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msedi

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Madshi

I cannot image that there would be a timer restriction in NT. How many timers do you have to create from a fresh boot of the system until you get the error?
Try to do something like this to test it:

var i1 : integer;
begin
for i1 := 0 to 10000 do
with TTimer.Create do
try
// here set all the properties
finally Free end;

Does this simple program fail, too? Then it's the proove that either the TTimer component or Windows itself has a bug or restriction.

Regards, Madshi.

oris

ASKER

I did some experiments, and there is a very good chance that I have a bug somewhere else in my program.

Martin,
I appreciate your efforts, so I will accept your comment as the answer.
Thanks,
Ori.
oris@math.tau.ac.il