Hi, this is Wayne again with a topic “What is CPU Cache?”.
When you think of memory in your computer, you might think of things like DVR modules, vram on your graphics card or most likely just hard drives and SSDs, but there’s actually another type of memory. That’S incredibly fast and essential to the speed that we’ve gotten accustomed to with modern computers. I’M talking about your CPU cache! No, not the money that you blew on that processor with hyper-threading that you didn’t really need. What we’re talking about is cache with an e. It’S a specialized type of memory, that’s built into your CPU, but why the heck would your processor need its own memory? Aren’T that 16 gigs of ram or whatever the heck you already have in your computer good enough? Well, not really! To be honest, you see those Ram modules are a heck of a lot faster than say a hard drive in terms of data transfer like a lot faster, but your CPU actually wants data much faster than your Ram can even provide it, and on top of that, As CPUs have gotten faster over the years, they continue to outstrip typical Ram modules by wider and wider margins, meaning that without faster memory, your CPU is going to be sitting around doing nothing like kind of unproductive employee as it waits for RAM and you’ll run into Bottlenecks as a result, this is where cache comes in unlike system memory, which consists of dynamic, RAM or DRAM. Your CPU cache is static, RAM or SRAM, which is more expensive and takes up more space, but is much faster than DRAM, because it doesn’t have to be constantly refreshed in order to hold data.
The way that DRAM has to be an average CPU will only have a few megabytes of cache, but it makes a tremendous use of this small amount of memory. You see when a CPU accesses something from your main system Ram. It generally stores it in its cache.
Then uses complex algorithms to guess as to what other instructions or data it might need next and it fetches those from your system Ram as well. Since these guesses aren’t perfect CPU suffer from things called cache misses where it searches its own. Cache can’t find what it needs and has to access your system memory directly instead, which slows things down. Fortunately, however, modern processors have gotten pretty good at deciding what to put inside their caches, as they’ll typically have a cache hit rate of better than 80 percent, meaning that most of the time, your CPU is only processing what it finds in cache and doesn’t have to Bother talking to your slower system memory at all and, as you may have guessed, more cache is advantageous.
So when you’re shopping for a processor, the product page will indicate how much level 3 or l3 cache is built-in, with higher-end modules having a few extra megabytes and if you’re wondering what the heck happened to levels 1. .