CPU的内部,一般也只有SRAM作为cache,不是主要的memory。 还有一种所谓的Memory Hierarchy。类似金字塔形状的结构,最大程度的优化速度和成本。可以去搜一下不同类型的memory。 最后,谈到CPU和GPU的区别。有一张特别出名的图片: 看CPU和GPU的结构对比。再加深一下对DRAM和SRAM的区分,这张图很能说明一些东西。比如,CPU...
Non-Exception-Generating指在Prefetch时不得引发Exception,包括Page Fault和其他各类的Memory Exception。在一些微架构中如果Prefech引发了Exception,获得的数据将被丢弃。此外Exception还会带来较大的Overhead,对Memory Consistency的实现制造障碍。 软件预读指令可以由编译器自动加入,但是在很多场景,更加有效的方式是由程序员...
memory and secondary memory memory and secondary memory Memory Hierarchy Memory Hierarchy Today’s computers each have small amount of Today’s computers each have small amount of very high very high--speed memory, called speed memory, called cache cache where where data from frequently used...
S.A. Przybylski, "Cache and Memory Hierarchy Design", Morgan Kaufmann Publishers Inc. 1990.Cache and Memory Hierarchy Design - Przybylski - 1990 () Citation Context ...largest increase possible with off-the-shelf memory parts -- with wider memory parts, the fetch size could be increased ...
在多数情况下,操作系统以4KB为单位将Memory分解为多个页面。如上图所示,这个4KB的页边界将Cache Line Index分解成两个部分,其中在Page Frame中的部分被称为Bin Index,在Page Off中的部分被本篇称为Offset Index。以此进行分析,Memory分配算法也被分为两大类,一类是Bin Index Aware,另一类是Offset Index Aware Memo...
处理器微架构访问Cache的方法与访问主存储器有类似之处。主存储器使用地址编码方式,微架构可以地址寻址方式访问这些存储器。Cache也使用了类似的地址编码方式,微架构也是使用这些地址操纵着各级Cache,可以将数据写入Cache,也可以从Cache中读出内容。只是这一切微架构针对Cache的操作并不是简单的地址访问操作。 为简化起见,...
上述公式中L是memory latency,S是执行一次循环迭代最短的时间。iterationAhead表示的是循环需要经过执行几次迭代,预取的数据才会到达Cache。假设我们的硬件架构计算出来的iterationAhead=6,那么原程序可以优化成如下程序: doublea[n];for(inti =0; i <12; i+=2)//prologueprefetch(&a[i]);for(inti =0; i <...
Cache and Its Importance in Performance • Motivation: –Time to run code = clock cycles running code + clock cycles waiting for memory –For many years, CPU’s have sped up an average of 50% per year over memory chip speed ups. ...
In their own side event this week, AMD invited select members of the press and analysts to come and discuss the next layer of Zen details. In this piece, we’re discussing the microarchitecture announcements that were made, as well as a look to see how this compares to previous...
Figure 5.Integrated FPGA PlatformMemory Hierarchy Figure 5shows the three level cache and memory hierarchy seen by anAFUin anIntegrated FPGA Platformwith oneIntel® Xeon®processor. A single processorIntegrated FPGA Platformhas only one memory node, the Processor-side:SDRAM(denoted(A.3)). The ...