When it comes to the processors in your business computers, is more better? It is if you want a lightning-fast machine. Multicore processors are CPUs (or cores) that have more than one processor on the same integrated circuit die (the piece of semiconducting material where a circuit is fabricated). Dual-core processors have 2 cores; quad-core processors have 4. Development in the “core-war” is continuing at a rapid pace. Six-core (aka “hex core”) and 8-core processors are available now, and it’s predicted that 16- and 64-core processors will be the norm in the future.
Generally speaking, the purpose of having multiple cores is to get more power to multitask with. When you’re using multiple programs on just one processor, traffic jams are easily created. In a multicore environment, each core has its own cache (the small memory space where oft-accessed data is stored) and its own front-side bus path (the path from the CPU to the RAM). These additional resources boost your computer’s power, allowing you to run intensive tasks in parallel.
The idea of tasks running in parallel is an important one. In a Windows system, the “scheduler” helps the CPU determine which program should be running, which allows it to switch between multiple programs as needed. The more programs a CPU is handling, the slower your computer becomes as its resources are stretched thin.
In a multicore system, you have a few advantages. First, there are more resources to handle intensive multitasking. You have two, four, or even six CPUs sharing the load. But another way multiple cores can speed up your processes is through something called thread-level parallelism. In simple terms, threads are part of an operating system or application that can run independently of one another. With applications that are multi-thread enabled — and most current OSes and some large software applications like Photoshop are — these threads can be handled by different processors, allowing even a single resource-intensive program to be handled by multiple cores simultaneously.
If you have some programs that aren’t multi-thread enabled, you can still utilize multiple cores if you’re running more than one program at a time. The only instance in which multiple cores might be wasted is if you’re only running a single, non-multi-thread enabled program at one time. But even then, your OS and other programs like antivirus software are running in the background and can take advantage of a second core.
While current OSes have prepared for this multicore future, much of the legacy software we use everyday has not. Developers are only beginning to explore the complexity of writing code to perform in a parallel computing environment. And so because most software hasn’t caught up, any cores beyond four are often wasted in today’s computers unless you’re primarily running video and imaging applications.
Two, Four, or More?
At this point, unless you’re purchasing a netbook for on-the-go Web surfing, any PC or laptop you buy will likely have at least a dual-core processor. So the question you need to ask yourself is, “Are two CPUs enough?” Do you need four or even more? As mentioned, moving to a six- or eight-core processor may be something to wait a few years for. And if you use a browser and word processor only, two should be enough. But for users who are unrepentant multitaskers, especially with resource-intensive programs like audio, video, or image editing software, or if you’re using your computer as a database or Web server, a quad-core may speed things up considerably. Also, it’s often helpful to buy a bit beyond your current needs so that your computer doesn’t become outdated too quickly.
But also remember that a CPU doesn’t act in isolation. Traffic jams can occur in any number of places. Cache, RAM, front-side bus, clock speed, video card — all these elements work in concert and affect speed. If one or more of these is too small or too slow, the number of cores you have won’t matter. So while it’s important to understand how each element affects speed and performance, know that all the components matter when you’re buying a new computer or upgrading a current model.