information systems study guide

lines of code (new/cumulative) Blog Volume ( new/cumulative) Learning time (new /cumulative) Goal 5000 rows 30 Articles 400 hours First week 100/100 1/2 10/10 Second week 150/200 2/4 8/18 Third week 200/250 1/5 5/23 Week Five 50/300 1/6 9/32 Week Six 20/320 1/7 8/40 Seventh Week

2018-2019-1 20165228 "The foundation of Information security system design" The second week study summary textbook learning content Summary information = bit + context Unsigned encoding: Represents a number greater than or equal to zero based on the traditional binary notation Complement coding: represents the most common way to sign a certificate, a number

important abstraction of the computer, which abstracts the physical storage space in the computer.Of course, this can also lead to some errors, such as the above mentioned in the C language of some errors, after understanding this knowledge can be better to help us to avoid some of the errors caused by storageLearning progress Bar lines of code (new/cumulative) Blog Volume ( new/cumulative) Learning time (new /cumulative) Goal 5000 rows 30 A

20145317 Peng Yao "Information Security system design basics" NO. 0 Week study SummaryFeelings:The relationship between the student and the teacher: fitness instructor and fitness trainee. Students want to build a good body but do not know the path and method, so to find the coach, the coach needs to do is to guide the students to correct exercise posture and exe

Sixth chapter. Memory hierarchyFirst, storage technology Three common storage technologies: Ram/rom/Disk Ram: RAM has SRAM and DRAM.(1) SRAM:(SRAM is used as a cache memory, either on the CPU chip or under the chip.) ）SRAM stores each bit in a bistable memory unit, each of which is implemented using a six-transistor circuit.Circuit Properties:Dual stability characteristics.Can be maintained indefinitely in one of two different voltage configurations or states, and an

time, metadata, by invoking the stat and FSTAT functions. #include The stat function takes a file name as input, and the ftast as input with a filename descriptor. Learning progress Bar Code lines (new/cumulative) Blog volume (new/cumulative) Learning Time (new/cumulative) important growth Goal 5000 rows 30 Articles 400 hours Seventh Week 1300/1750 11/11 140/140

blocked, waiting for a condition that will never be true. Programmers use P and V incorrectly so that two of the semaphore's forbidden areas overlap. Overlapping forbidden areas cause a set of states called deadlock zones. Deadlocks are unpredictable. This week's code hostingResources "In-depth understanding of computer system V2" Learning Guide 2016-2017-1 the teaching process of the basic design of

specified as a double word, the size of the block is the integer multiple of the double word, not the rounding to Yes.Explicit idle linked list Difference（1）分配时间 隐式的，分配时间是块总数的线性时间 但是显式的，是空闲块数量的线性时间。（2）链表形式 隐式——隐式空闲链表 显式——双向链表，有前驱和后继，比头部脚部好使 Sorting policy:?后进先出?按照地址顺序维护Detached List of idle links Separating storage is a popular way to reduce allocation time. The general idea is to divide all possible block sizes into equivalent class/size classes The allocator maintains an a

particular trajectory through the execution state space, forgetting a guideline that the threaded program must work correctly for any viable trajectory.2. Elimination Method:Dynamically assigns a separate block to each integer ID, and passes to the thread routine a pointer to the block4. Deadlock1. A set of threads is blocked, waiting for a condition that will never be true. Programmers use P and V to operate improperly so that the forbidden areas of two semaphores overlap. Overlap

that is a member of the size class.This method is fast and efficient for memory use.3. Partner Systems　　Each of these size classes is a power of 2Thus, given the size of the address and block, it is easy to calculate the address of its partner, that is to say: The address of a block and its partner's address only a different.Pros: Quick Search, quick merge.9.10 Garbage CollectionThe garbage collector is a dynamic storage allocator that automatically

exception. The typical errors are:scanf("%d",val); (2) Read uninitialized memory Although the bass memory location is always initialized to 0 by the loader, it is not the case for heap storage. A common mistake is to assume that the heap memory is initialized to 0. (3) Allow stack buffer overflow If a program writes to the target buffer in the stack without checking the size of the input string, the program will have a buffer overflow error. (4) Assume t

20145317 "Information Security system Design Fundamentals" 7th Week study summary 1 Textbook Learning content SummaryBasic storage technology: SRAM memory DRAM memory ROM memory rotary hard drive SSD1. Storage TechnologyThree common storage technologies: ram/rom/disk( 1 ) random access memory RAM Two categories: Static RAM (SRAM) and dynamic RAM (DRAM) Static RAM (SRAM) is faster, but much more

after the completion of Y86 in the pipe folder input./PSIM-T-G. /y86-code/asum.yoEnter Y86-code, Generate Asuml.yoI try to knock the code out of the book, and then enter the following commandmake cleanmake 251pp.yoYou can then view the　　Code Managed Links: http://git.oschina.net/Zziyang/CS04Learning progress Bar lines of code (new /Cumulative) Blog volume ( new/cumulative) Learning time (new/cumulative) Important growth Goal 5000 row

unsigned number to a larger data type, representing the beginning plus 0.Symbol extension-Converts a complement number to a larger data type.Three, integer arithmeticUnsigned number additionAn arithmetic operation overflow that indicates that a complete integer result cannot be placed into the word length limit of the data type.Multiply Constants either unsigned or complement operations, multiplying by a power of 2 results in overflow. Four, floating point numberWhen a number cannot be accurate

Information Security system design basics first week study summaryI. Introduction to the History of experiments1. Knowledge points1) Operating system: Connect hardware and applications as a bridge between the computer tables, including system calls and cores.2) Linux: Developed by the first, the original purpose isCompared to Windows, the main advantages (and some people's serious disadvantage) are-mostly o

manipulating processes:STRACE：打印一个正在运行的程序和它的子进程调用的每个系统调用的轨迹。对于好奇的的工具。用-StatiC编译你的程序，能传到一个更干净的、不带学生而言，这是一个令人着迷有大量与共享库相关的输出的轨迹。PS：列出当前系统中的进程（包括僵死进程）TOP：打印出关于当前进程资源使用的信息。PMAP：显示进程的存储器映射。proc:一个虚拟文件系统，以ASCII文本格式输出大量内核数数据结构的内容，用户程序可 cat 2 / proc / load avg” , 观察在Linux系统上的平均负载。SummarizeThis week to learn more content, the front also read more understand, behind some chaos, I hope the teacher in class to talk about non-local jump knowledge, I still do not understand here.ResourcesTextbook: "In-depth u

fast.The minimum number of cache misses is within each loop.2. Repeated references to local variables are good because the compiler is able to cache them in a register file (temporal locality).3. The reference pattern of step 1 is good because the cache at all levels in the memory hierarchy is storing the data as contiguous blocks (spatial locality).Reference: 1. "In-depth understanding of computer Systems", chapter sixth2. Experimental building cour

Information Security System Design Foundation 14th Week study Summary"Learning Time: 7 hours""Learning content: chapter9--virtual Memory"First, the content of the textbook Understanding (Personal Understanding section with "" marked) 1. Virtual Storage (VM) function : The main memory is considered as a cache of the address space stored on disk, only the active area is protected in main m

2018-2019-1 20165228 "Fundamentals of Information Security system design" the third week of learning summary of the Learning Content Summary program machine-level representation: Two important abstractions of computer systems ISA (Instruction set architecture): Instruction set architecture, machine-level program format and behavior. Defines the format of the processor status directives and the effe

Who commandWho reads the desired information into the memory and then prints it to the screen using the standard output function, closing the file.View pre-logon user-who am I;Lists the logged-on user-who or-W.Error Handling in UNIX systems UNIX style: For example, the fork function and the coat function, the return value includes both the error code and useful results.if((pid = wait(NULL)) POS