Steve Jobs on Apple Operating System Strategy
What Jobs talks about
Jobs explains how Rhapsody is structured: a PowerPC-native core operating system built on the Mach microkernel, with networking, file I/O, preemptive multitasking, and protected memory at the foundation.
He emphasizes that the system is designed to run on both Apple’s shipping Macintosh systems and compatible machines sold by licensees, while delivering modern system services and performance improvements.
A major point is compatibility: the Mac OS compatibility box re-hosts the same Mac OS source code on top of the modern microkernel, preserving existing Macintosh software while moving to a new OS architecture.
Jobs speaks throughout.
In his words
“It's built on the PowerPC processor and runs on the Macintosh systems that we're shipping today.”
“This layer is completely PowerPC native, so this is where you get the performance improvements.”
“This is not an emulator of Mac OS, but in fact, this is the same source code that we ship as Mac OS, but re-hosted on top of the modern microkernel.”
“This is what gives us very good backwards compatibility for existing Macintosh software.”
Key points
- Rhapsody is built on PowerPC and runs on current Macintosh hardware.
- The core OS is based on the Mach microkernel.
- The core layer provides networking, file I/O, preemptive multitasking, and protected memory.
- Apple’s modern OS is PowerPC native for better performance.
- Mac OS compatibility is preserved through a compatibility box, not emulation.
- Existing Mac OS source is re-hosted on top of the modern microkernel.
- OpenSTEP is another major service layered on top of the core OS.
Full transcript
Now, let's take a look at some of the details about how Rhapsody actually works. It's built on the PowerPC processor and runs on the Macintosh systems that we're shipping today. It also runs on the Macintosh compatible systems that are sold by our licensees today. The next layer up is the core operating system itself. That's based on the mock microkernel, and this handles your networking, your file I.O. This layer is completely PowerPC native, so this is where you get the performance improvements. This is also what gives us some of the low-level system services, like preemptive multitasking and protected memory. Built on top of the core OS are two major services. First is the Mac OS compatibility box, shown on the diagram here as the blue box.
This is what gives us very good backwards compatibility for existing Macintosh software. This is not an emulator of Mac OS, but in fact, this is the same source code that we ship as Mac OS, but re-hosted on top of the modern microkernel. Also on top of the core OS is the OpenSTEP programming module. This is what gives us very good backwards compatibility for existing Macintosh software. This is not an emulator of Mac OS, but in fact, this is the same source code that we ship as Mac OS, but re-hosted on top of the modern microkernel. This is what gives us very good backwards compatibility for existing Macintosh software.
This is what gives us very good backwards compatibility for existing Macintosh software. This is what gives us very good backwards compatibility for existing Macintosh software. This is what gives us very good backwards compatibility for existing Macintosh software.
Transcribed from the audio with OpenAI Whisper. Timestamps link to the video above. Errors are possible.