What is the three level cache in the CPU

A level three cache is designed to read data that is not hit by a level two cache, where only about 5% of the data in a CPU with level three cache needs to be called from memory, which further increases CPU efficiency. It works by using a faster storage device to keep a copy of the data read from a slow storage device, when it is necessary to read and write data from the slower storage, the cache can enable the read and write action to be done on the fast device first, so that the system responds more quickly.

Classification

Cache (Level three buffer), divided into two, the early is external, later upgrade products are built. In fact, the application of the L3 cache can further reduce the memory latency and improve the performance of the processor while calculating the large amount of data. Reducing memory latency and increasing the ability to compute large amounts of data can be very helpful to the game. Increasing the L3 cache in the server domain still has a significant performance improvement. For example, a configuration with a larger L3 cache uses physical memory more efficiently, so its slower disk I/O subsystem can handle more data requests. Processors with larger L3 caches provide more efficient file system caching behavior and shorter message and processor queue lengths.

In fact, the earliest L3 cache was applied to the AMD-released K6-III processor, when the L3 cache was limited to the manufacturing process and was integrated into the motherboard instead of being integrated into the chip's interior. The L3 cache, which can only be synchronized with the system bus frequency, is not much worse than the main memory. The L3 cache was later used by Intel as an Itanium processor for the server market. Then there is the P4ee and Xeon MP. Intel also intends to launch a 9MB L3 cache Itanium2 processor, and a dual-core Itanium2 processor for later 24MB L3 caching.

But basically the L3 cache is not very important to the performance of the processor, for example, the Xeon MP processor with 1MB L3 cache is still not an opponent of Opteron, this shows that the increase in the front-end bus is more efficient than the increase in cache performance.

Performance impact

Level three cache has a high performance impact when low. In the game aspect, the enhancement level three cache capacity has the very big influence to the game performance, although to the general household machine does not have any use, but if is the Internet Café machine or is the Fever machine to raise the three level cache the capacity or will have the remarkable performance enhancement. Although the level three cache can also bring significant performance improvements to your PC, but after all, the level three cache is for the server, for the PC, the level three cache can only do a secondary role, in the same case, the three cache capacity is greater, the performance is better, if other parameters are not the same, At this time, the function of level three cache is not obvious.

Regardless of the magnitude of the three cache, it is also one of the parameters contributing to the development of the computer.