CPU performance mainly depends on the core number, CPU architecture, CPU frequency and cache synthesis. Usually these values are as large as possible. Among them, we have a good understanding of the number of cores, architecture and frequency. However, we still have a lot of questions about caching. For example, what are the more secondary caches and the difference between L2 cache and L3 cache? More, the following article is a detailed explanation of the problem.
cache works is when the CPU to read a data, first from the cache, if found immediately read and sent to CPU processing; if not found, use a relatively slow speed from memory The data is read and sent to the CPU for processing. At the same time, the data block where the data is located is transferred into the cache, so that the reading of the entire block of data can be performed from the cache in the future, and the memory does not need to be called.
CPU usually has a cache, L2 cache, and three-level cache is said, we were introduced to the following: to coordinate the emergence of cache and memory of
secondary cache (L2CACHE) The speed between. Initially the cache was only one level, and later the processor speed increased, the level 1 cache was not enough, so the second level cache was added. The second level cache is a slower and higher capacity memory than the first level cache, and is mainly used for the temporary exchange of data between the level 1 cache and the memory. The L3 cache is designed for reading data that is missed after the L2 cache. In a CPU with a L3 cache, only about 5% of the data needs to be called from memory, which further improves the CPU efficiency.
current AMD processors generally only a secondary cache, no L3 cache. Intel mainstream processors usually have second- and third-level caches, but the second-level cache is smaller, and the third-level cache is larger. For example, the mid-range popular i3 processor has a second-level cache of 512K, the third-level cache is 3M, and the Intel high-end. The processor mainly has one-level and three-level cache, and the third-level cache is up to 6M, 8M, etc., but both the AMD processor and the Intel processor level 1 cache are fixed and not large.
Overall, the decision CPU performance is determined by the number of CPU cores, clock speed, CPU architecture, as well as the CPU cache, in general, Intel architecture aspects of technical advantages, AMD processors there The core number advantage, the second and third level cache is also the details of determining the performance of the CPU, but it is not a decisive factor. And the AMD processor's performance improvement on the L2 cache is smaller than that of Intel, which is mainly due to the advanced technology of Intel technology. The third-level cache is originally the thing on the server, and it still shows the effect by the corresponding system and software influence. At present, Intel high-end processors generally have large-capacity three-level cache, usually three-level cache up to 8M.