The most basic game loop is like this :

while(1)
{
   update();
   draw();    
   swapbuffers();
}

This is very simple but have a problem : some drawing commands can be blocking and cpu will wait while he could do other things (like processing next update() call).

Another possible solution i have in mind would be to use two threads :

one for updating and preparing commands to be sent to gpu, and one for sending these commands to the gpu :

//first thread
while(1)
{
   update();
   render(); // use gamestate to generate all needed triangles and commands for gpu 
             // put them in a buffer, no command is send to gpu
             // two buffers will be used, see below
   pulse(); //signal the other thread data is ready
}

//second thread
while(1)
{
   wait();              // wait for second thread for data to come
   send_data_togpu();   // send prepared commands from buffer to graphic card
   swapbuffers();      
}

also : two buffers would be used, so one buffer could be filled with gpu commands while the other would be processed by gpu.

Do you thing such a solution would be effective ? What would be advantages and disadvantages of such a solution (especially against a simpler solution (eg : single threaded with triple buffering enabled) ?