Automatic switching of embedded and discrete graphics in MacBook Pro

I think everyone noticed the new automatic graphics switching system in the new MacBook Pro 15/17. Some immediately thought that this was just NVIDIA Optimus technology, but this is not entirely true.
The main purpose of switching between video cards is to balance the graphic power and battery life. The latest models of Intel Core i3, i5, and i 7 processors include the integrated Intel HD graphics chip. It is clear that there is no point in waiting for a miracle from the new chip, and its performance is only slightly higher than the old GMA950 , however this chip handles the main tasks perfectly and does not require large power consumption, and another one is not required of it.


As we all remember, in the previous MacBook Pro series, Apple had already attempted to implement a solution for automatically switching between embedded and discrete graphics. However, this implementation cannot be called correct. Judge for yourself: in order to switch the graphics, you had to go to System Preferences and manually switch it. That's not all! Then, you had to close all your applications, make a log off and back log in . How do you think, how many people used it all? I think a little. Too many gestures are required, and hardly anyone wants to interrupt their work and close all programs.
Other companies have solved the problem in their own way. Some managed to reduce the time to switch between video cards, and to abandon Log Off-Log In , however, there was still no instant switching, the work, though not for long, was interrupted. AMD / ATI used the following method: if the laptop was connected to the network, then discrete graphics were turned on; if turned off, the integrated ones were turned on. Yes, the solution, of course, is not ideal, because in fact it tied users to sit at the outlet to launch any heavy application.

NVIDIA Optimus is built differently. This technology uses both hardware and software graphics switching. NVIDIA accomplished this by creating lists of software that divides software into something that needs discrete graphics and something that is enough for an integrated graphics chip. NVIDIA itself is responsible for the relevance of this list, it is automatically updated from the company's website. Yes, the user, of course, may himself edit this list in the settings, but in most cases it will not be necessary to do this. Of course, it was not without its drawbacks: Optimus works with the always-on integrated graphics. When Optimus turns on discrete graphics, it starts using an integrated chip buffer, which in turn is in your RAM. This means that with high performance there will be a large amount of unnecessary “traffic” to the bus. So Apple technology differs from Optimus in two things.
First , the switching is fully automatic, controlled by Mac OS X and does not require user intervention (of course, no more Log Off-Log In). Of course, the user can disable this behavior in the OS settings. Applications that use OpenGL, Core Graphics, Quartz Composer, and other technologies may “ask” the OS to enable discrete graphics. Therefore, if you read mail in Mail, then you use the built-in video chip, but if you open any website on flash ... Oh, not that! So, if you open any heavy application like Aperture or Photoshop, Mac OS X will immediately turn on your NVIDIA GeForce GT 330M for maximum performance.
Well, the second difference is that Apple technology disables the integrated graphics when using discrete, which helps, as you understand, to extend the operating time of your laptop without an outlet to 8-9 hours . Of course, Apple would not have been able to achieve such integration if it had not controlled both the hardware and software components of its products. Other vendors in this sense will be much harder. ( c )