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How to get a thread's execution time

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Join Date: Jun 2009

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wildgoose

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Re: How to get a thread's execution time

#11

Jul 6th, 2009

When you spawn the thread you pass a void user value!
Why not pass a boolean pointer! Loop while it is set and when false fall out of the thread loop. Don't forget your thread exit function for proper cleanup.

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 C++ Syntax (Toggle Plain Text) 
void MyWorker( void *foo )
{
    bool *pbSignal = (bool *)foo;
 
   while (foo)
   {
 
 
   }
 
}
void MyWorker( void *foo )
{
    bool *pbSignal = (bool *)foo;

   while (foo)
   {


   }

}

Or pass in a local index for that worker thread.

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 C++ Syntax (Toggle Plain Text) 
void MyWorker( void *foo )
{
    uint idx = (uint)foo;
 
   while ( gbAppActive == true )
   {
 
 
   }
 
   gThreadActive[ idx ] = false;  // Tell root that this thread is shut down
 
}
void MyWorker( void *foo )
{
    uint idx = (uint)foo;

   while ( gbAppActive == true )
   {


   }

   gThreadActive[ idx ] = false;  // Tell root that this thread is shut down

}

In application root cleanup.
Loop for up until all gThreadActive[] become clear or the clock runs out, whichever comes first.

If you use semaphores, use a single gThreadActive parameter and merely clear the bit!

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 C++ Syntax (Toggle Plain Text) 
LOCK();
gThreadActive ^= 1 << idx;
UNLOCK();
LOCK();
gThreadActive ^= 1 << idx;
UNLOCK();

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Join Date: Sep 2008

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rmlopes

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Re: How to get a thread's execution time

#12

Jul 7th, 2009

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When you spawn the thread you pass a void user value!
Why not pass a boolean pointer!

When you spawn the thread you pass a void pointer, which means you pass a pointer to something (or nothing). I am already using this to pass some arguments to the threads.
Wildgoose, I don't get what this last post has to offer to the discussion.

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Ancient Dragon Ancient Dragon is offline

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Re: How to get a thread's execution time

#13

Jul 7th, 2009

I don't understand what's so difficult about thread timing. If you want the thread to quit after a specified amount of time, then just compare current time with original thread entry time and exit when that difference is greater than some pre-determined amount of time.

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Join Date: Sep 2008

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rmlopes

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Re: How to get a thread's execution time

#14

Jul 7th, 2009

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Originally Posted by Ancient Dragon

I don't understand what's so difficult about thread timing. If you want the thread to quit after a specified amount of time, then just compare current time with original thread entry time and exit when that difference is greater than some pre-determined amount of time.

I don't understand what's so difficult about multi-threading for you. Threads yield execution to other threads and gain it back and yield again... etc. When they yeld they are not running anymore so any "raw" difference between starting time and current time is *not* what you want. Stop insisting please... I would flag your last post as a bad post...

NOTE: as mentioned in a previous post this issue can be solved in UNIX by using clock_gettime with the flag CLOCK_THREAD_CPUTIME_ID. I don't even need to save the start point because each thread's clock is set to 0 when it starts. I made the tests, 10 threads executing for 50 seconds in a core-duo processor, giving total time ~= 250 seconds, perfect for me!
I am still looking for a solution which can be applied cross-platform, or at least a similar solution for windows.