shashwat shriparv [email protected] infinitysoft
TRANSCRIPT
AGENDA:Processor: Overview
Speed Vs Performance
Multi-Core Processors
Examples
The Architecture
Pros & Cons
Future…
Processor: Overview A single chip package that fits in a socket. Each
processor chip integrated with a no. of transistors.
≥1 core (not much point in <1 core…)◦ Cores can have functional units, cache, etc.
associated with them◦ Cores can be fast or slow
Shared resources◦ More cache◦ Other integration: memory controllers, high-speed serial
links, etc.
Processor: Diagram
Processor: History….
"The number of transistors and resistors on a chip doubles every 18 months." By Intel co-founder Gordon Moore regarding the pace of semiconductor technology. He made this famous comment in 1965 when there were approximately 60 devices on a chip. Proving Moore's law to be rather accurate, four decades later, Intel placed 1.7 billion transistors on its Itanium chip.
MOORE’S LAW
Speed vs. Performance
A multi-core CPU (or chip-level multiprocessor, CMP) combines two or more independent cores into a single package composed of a single integrated circuit (IC), called a die, or more dies packaged together.
A multi-core microprocessor implements multiprocessing in a single physical package. Multi-core architecture has a single processor package that contains two or more processor "execution cores," or computational engines, and delivers—with appropriate software—fully parallel execution of multiple software threads.
The New Era: Multi Core Processors
Cores in a multi-core device may share a single coherent cache at the highest on-device cache level (e.g. L2 for the Intel Core 2) or may have separate caches (e.g. current AMD dual-core processors). The processors also share the same interconnect to the rest of the system.
The operating system (OS) perceives each of its execution cores as a discrete processor, with all the associated execution resources.
Each "core" independently implements optimizations such as superscalar execution, pipelining, and multithreading
Continued….
A dual-core processor contains two cores and a quad-core processor contains four cores. Dual-core processors are the first step in the transition to multi-core computing.
Intel is already conducting research on architectures that could hold dozens or even hundreds of processors on a single die
By enabling energy-efficient performance and more-efficient simultaneous processing of multiple tasks, multi-core processors promise to improve user experiences in both home and business environments.
Multi-Core is the future of computing
Continued….
ARCHITECTURE
Single-core processor
Multi –Core processor
Working….
Core Components
Functional unitsSuperscalar is known territory. Diminishing returns for adding more functional blocks. Single-threaded architectural performance is pegged
Data pathsIncreasing bandwidth between functional units in a core makes a difference. Such as comprehensive 64-bit design.
Core Components….
PipelineDeeper pipeline buys frequency at expense of increased cache miss penalty and lower instructions per clock. Shallow pipeline gives better instructions per clock at the expense of frequency scaling. Max. frequency per core requires deeper pipelines
CacheCache size buys performance at expense of die size. Deep pipeline cache miss penalties are reduced by larger caches.
Increased computing CapabilitiesMulti-core processors allow to complete
today's computing tasks more efficiently and will enable entirely new computing experiences, and the benefits apply to server and client platforms, as well as the home and enterprise environments. Multi-core capability can enhance user experiences in multitasking environments, namely, where a number of foreground applications run concurrently with a number of background applications such as virus protection and security, wireless, management, compression, encryption and synchronization.
Advantages
Higher Performance
First with multiprocessor platforms and then with Hyper-Threading Technology¹ (HT Technology), which was introduced by Intel in 2002 and enables processors to execute tasks in parallel by weaving together multiple "threads" in a single-core processor. But whereas HT Technology is limited to a single core using existing execution resources more efficiently to better enable threading, multi-core capability provides two or more complete sets of execution resources to increase overall compute throughput.
Advantages…..
The digital home & BusinessWith ever-growing numbers of networked PC
and consumer electronics devices, will increasingly depend on the multitasking capabilities of multi-core processors to handle the demands of orchestrating the different networked TVs, stereos, cameras, and other devices and appliances in the household. Multi-core is also taking gaming to a whole new level, and will also make multiparty gaming ubiquitous. Tomorrow's computers will be powerful enough to run multiparty gaming and collaboration on their own.
Advantages…..
Quality software developmentLeading software vendors and corporate
developers to enable multithreaded code that can take full advantage of the increased capabilities of multi-core processors. As a result, we've established extensive multithreading tools, education resources, and experience-based technical expertise that have helped drive thread-optimization across a wide range of applications
Advantages…..
Adjustments to the existing softwareIn addition to operating system (OS) support,
adjustments to existing software are required to maximize utilization of the computing resources provided by multi-core processors. Also, the ability of multi-core processors to increase application performance depends on the use of multiple threads within applications. For example, most current video games will run faster on a 3 GHz single-core processor than on a 2GHz dual-core processor (of the same core architecture)
Limitations
Thermal managementIntegration of a multi-core chip drives
production yields down and they are more difficult to manage thermally than lower-density single-chip designs. From an architectural point of view, ultimately, single CPU designs may make better use of the silicon surface area than multiprocessing cores, so a development commitment to this architecture may carry the risk of obsolescence.
Limitations…..
Intel ProcessorsoPentium DoPresleroYonahoMontecitooPaxvilleoDempsey etc…
AMD ProcessorsoAMD OpteronoAMD TurionoAMD Sempron etc..
Examples……
Example>>>
Comparison
Past...Present…Future
