Timing delays in a double data rate (DDR) dynamic random access memory (DRAM) controller (114, 116) are trained. A left edge of passing receive enable delay values is determined (530). A final value of a receive data strobe delay value and a final va…

Computer Systems A Programmer's Perspective Second Edition As we will discuss, the extension of IA32 to 64 bits, termed x86-64, was origi- nally developed by Advanced Micro Devices (AMD), Intel's biggest competitor. Whereas a 32-bit machine can only…

Random Access Iterator \[ Time Limit: 4000 ms \quad Memory Limit: 262144 kB \] 题意 给出伪代码,问按着伪代码在树上跑,能够正确求出来树的深度的概率. 思路 先在树上 \(dfs\) 一遍,求出每个点可以走到的最深深度,用 \(deep\) 表示. 令 \(dp[i]\) 表示从 \(i\) 节点能够正确求出最深深度的概率. 如果 \(deep[u]\) 不等于最深深度,那么明显 \(dp[u]=0\) 如果 \(de…

以太坊MPT树的持久化层是采用了leveldb数据库,然而在抽取MPT树代码运行过程中,进行get和write操作时却发生了错误: Caused by: org.fusesource.leveldbjni.internal.NativeDB$DBException: IO error: C:\data\trie\.sst: Could not create random access file. at org.fusesource.leveldbjni.internal.NativeDB.che…

Random Access Iterator 树型概率DP dp[u]代表以当前点作为根得到正确结果的概率 将深度最深的几个点dp[u]很明显是1 然后很简单的转移 有k次,但我们要先看一次的情况,然后再推到k次,k次中只要有一次就可以正确,所以求出k次全失败的概率,用1去减即可 #include <bits/stdc++.h> #define ll long long using namespace std; const int maxn = 1e6+7; const int mod = 1…

问题描述:        把列表listview写入notebook里. 在main函数中, win = create_and_set_a_window(); book = gtk_notebook_new(); gtk_notebook_set_tab_pos( GTK_NOTEBOOK( book ), GTK_POS_LEFT ); gtk_container_add( GTK_CONTAINER( win ), book ); create_page_one( book, win );…

题目链接 大致题意:从根节点出发,在节点x有son[x]次等概率进入儿子节点,求到达最深深度的概率.son[x]为x节点的儿子节点个数. 又又又又没做出来,心态崩了. 下来看了官方题解后发觉自己大体思路是没错的,但是细节太弱了Orz. 大体思路:设dp[x]为以x为根节点,求到达最深深度的概率.先跑一遍dfs,求出每个点的子节点数,每个点的深度以及最深深度. 我们可以求得从x点一次不能到达最深深度的概率为$cnt =1-(\tfrac{\sum_{y\epsilon x } dp[y]}{son…

每次循环向下寻找孩子时,随机选取一个孩子,设dp[u]为从u出发,不能得出正确答案的概率,则从u出发,走一次的情况下不能得出正确答案的概率是 P = (dp[v1]+dp[v2]+dp[v3]+--dp[vk]) / cnt_son[u] ,则从u出发,要走cnt_son[u]次,那么dp[u]=P^cnt_con[u] dp的意义也可以改成能得出正确答案的概率,下面的式子稍微改改就行了 为了避免除法的精度问题,num/k %mod,它等于 num * ni %mod ,ni等于k在模mod意义…

A system and method for accessing memory are provided. The system comprises a lookup buffer for storing one or more page table entries, wherein each of the one or more page table entries comprises at least a virtual page number and a physical page nu…

Methods, apparatus, and systems, including computer programs encoded on a computer storage medium, manage an address space. In some implementations, a method includes managing an allocation data structure for a memory, wherein the allocation data str…

BACKGROUND OF THE INVENTION Conventional NAND Flash memories move data in the background to write over an entire span uniformly. The background data movement is called wear leveling. A process performing the background data movement is often referred…

BACKGROUND INFORMATION Various mechanisms exist for managing memory in a virtual machine environment. A virtual machine platform typically executes an underlying layer of software called a virtual machine monitor (VMM) which hosts one to many operati…

A processor, capable of operation in a host machine, including memory management logic to support a plurality of memory types for a physical memory access by the processor, and virtualization support logic to determine a host memory type for a refere…

A processor including a virtualization system of the processor with a memory virtualization support system to map a reference to guest-physical memory made by guest software executable on a virtual machine which in turn is executable on a host machin…

A processor including a virtualization system of the processor with a memory virtualization support system to map a reference to guest-physical memory made by guest software executable on a virtual machine which in turn is executable on a host machin…

Executing a Next Instruction Access Intent instruction by a computer. The processor obtains an access intent instruction indicating an access intent. The access intent is associated with an operand of a next sequential instruction. The access intent…

Methods, systems, and products for governing access to objects on a filesystem. In one general embodiment, the method includes providing a framework in an operating system environment for support of a plurality of access control list (ACL) types, the…

文章首发于浩瀚先森博客http://www.guohao1206.com/2016/12/07/1248.html 说到计算机上的存储器,很多人第一反应是硬盘,然后是内存. 其实在计算机上除了硬盘和内存属于存储器以外CPU寄存器和Cache他们也是属于一类的. 对于存储器我们在乎的无外乎两个属性----"快"和"大",我们希望存储器容量越大越好,传输速度越快越好,然后鱼和熊掌不能兼得.由于现在硬件技术的限制,我们能制造错容量虽小但是速度很快的存储器,也可以制造出容量…

目录 . 简介 . 进程虚拟地址空间 . 内存映射的原理 . 数据结构 . 对区域的操作 . 地址空间 . 内存映射 . 反向映射 .堆的管理 . 缺页异常的处理 . 用户空间缺页异常的校正 . 内核缺页异常 . 在内核和用户空间之间复制数据 1. 简介 用户层进程的虚拟地址空间是Linux的一个重要抽象,它向每个运行进程提供了同样的系统视图,这使得多个进程可以同时运行,而不会干扰到其他进程内存中的内容,此外,它容许使用各种高级的程序设计技术,如内存映射,学习虚拟内存,同样需要考察可用物理内存中…

It’s coming up on a year since we published our last memory review; possibly the longest hiatus this section of the site has ever seen. To be honest, the reason we’ve refrained from posting much of anything is because things haven’t changed all that…

A data processor supports the use of multiple memory models by computer programs. At a device external to a data processor, such as a memory controller, memory transactions requests are received from the data processor. Each memory transaction reques…

BACKGROUND Advances in semi-conductor processing and logic design have permitted an increase in the amount of logic that may be present on integrated circuit devices. As a result, computer system configurations have evolved from a single or multiple…

A collection of multiple user credentials each associated with one of multiple different users is obtained at a device, and one or more of the multiple user credentials are verified. A determination is made as to whether access to a resource is permi…

BACKGROUND OF THE INVENTION A conventional virtual-machine monitor (VMM) typically runs on a computer and presents to other software the abstraction of one or more virtual machines. Each virtual machine may function as a self-contained platform, runn…

A method and apparatus for preserving memory ordering in a cache coherent link based interconnect in light of partial and non-coherent memory accesses is herein described. In one embodiment, partial memory accesses, such as a partial read, is impleme…

A method includes storing, with a first programmable processor, shared variable data to cache lines of a first cache of the first processor. The method further includes executing, with the first programmable processor, a store-with-release operation,…

A role-based access control (RBAC) modeling and auditing system is described that enables a user to access and/or create security roles that can be applied to users of a first software application. When a security role having a particular set of perm…

A trusted computer system that offers Linux® compatibility and supports contemporary hardware speeds. It is designed to require no porting of common applications which run on Linux, to be easy to develop for, and to allow the use of a wide variety of…

Systems and methods are provided to manage risk associated with access to information within a given organization. The overall risk tolerance for the organization is determined and allocated among a plurality of subjects within the organization. Allo…

Virtual addresses from multiple address spaces are translated to real addresses in main memory by generating for each virtual address an address space identifier (AID) identifying its address space. Then, the virtual address and its AID are used to o…