computer os systems

Today, colleagues want to install 64-bit Win7, do not know whether their computer support 64-bit system, we see it may not be easy to see directly, the following two methods to do simple judgment and verification. 1, simple method of judgment is, if you believe that you are dual-core or dual-core CPU, basically can be judged to be able to support 64-bit; If you don't know, you can right-click "My Computer

JavaScript access to client computer hardware and system InformationAccess to client computer hardware and system information through WMI: Copy Code code as follows: function Getsysinfo () { var locator = new ActiveXObject ("WbemScripting.SWbemLocator"); var service = Locator. ConnectServer ("."); CPU Information var CPU = new Enumerator (service. ExecQuery ("SELECT * from Win32_Proce

pic code 13. Tools for processing target files14. Summary　　Links can be done at compile time by a static compiler, or by a dynamic linker at load time and at run time. The linker processes the binary file that becomes the target file, and it has three different forms: relocatable, executable, and shared. The relocatable target file is merged into an executable target file by a static linker, which can be loaded into memory and executed. Shared destination files (shared libraries) are linked an

Tiny server-1: an in-depth understanding of computer systems I recently learned Chapter 1 network programming in "deep understanding of computer systems". The last section is the implementation of a small web server named Tiny, which has been provided in the source code book, here we will not copy and paste it. This bl

computer systems limit the location of basic types of data in memory, and they require that the value of the first address of the data be a multiple of a number k (usually 4 or 8), which is called memory alignment, and this k is called the Zimo number of the data type (alignment modulus). When the ratio of one type S pair of Zimo number to the Zimo number of another type T is an integer greater than 1, we

address space and a physical address selected from the Physical address space.Virtual memory as a tool for cachingConceptually, the virtual memory is organized into an array of cells that are taken down by n contiguous bytes stored on disk. Each byte has a unique virtual address, and this unique virtual address is used as an index to the array. The contents of the array on disk are cached in main memory. As with other caches in the memory hierarchy, the data on the disk is partitioned into bloc

:　　　　　　　　　　　　　　　　　　　　　　　　Operations: Order, number of positions and (difference), normalization of results and judging overflow (mantissa), rounding processing, overflow judgment (order code)Check code　　To detect whether the transmitted data is reliableParity check Code (parity code): Horizontal parity check code, vertical parity check code, horizontal vertical parity check codeSea-PlainTextCyclic redundancy Check CodeII. System StructureMacroscopic, according to the processor quantity classific

exclude the range of values in non-normalized, because those values are all less than 1. In the range of values that are considered normalized, if a n+1 decimal is required and is the smallest decimal, it should consist of a 1 of n 0 and the lowest bit. That is, the mantissa m = 1 + F = 1 + 2-n-1, when we use the order to cancel out the decimal place, the order code is 2n+1, so the last value is 2n+1+1.Let's take an example to consider the simplest, for example, when n is 1 o'clock, the value i

... TDK, you can start the nextData block transfer of the device.The time required to complete the data transfer for all devices is:The Limit flow is:3.6 Channel Actual flow analysis(1) byte multi-channelBecause each device on the channel has a small piece of time, the actual traffic for the channel is the sum of all device traffic.Fi is the flow of the first equipment(2) Select Channel and array multichannel channelBecause a channel can serve only one device over a period of time, the traffic

user address and grows downward (to the low memory place). The segment that starts at the top of the stack is reserved for code and data for the part of the operating system that resides in the memory (that is, the kernel).10. Dynamic Link Shared libraryShared library is a modern innovation product that devotes to solving the defect of static library. A shared library is a target module that, at run time, can be loaded into any memory address and added to a program in memory to link it up. This

information about the field declaration or the field name.3. Union: Allows you to reference an object in multiple types, using different fields to refer to the same memory block. The total size of a union equals the size of its maximum field. Unions can also be used to access bit patterns for different data types.4. Data alignment: A type object must be a multiple of a K value (usually 2,4 , or 8). This alignment restriction simplifies the hardware design that forms the interface between the pr

logical operation is any nonzero, false is 0Expression result!0x41 0x00!0x00 0x01!! 0x41 0x010x69 0x55 0x010x69 | | 0x55 0x01C language Shift operationsThe general machine supports two right-shift operations:Logical Right Shift: Move right, discard right, left end 0Arithmetic Right Shift:move right, discard right side, left end to fill the value of the most significant bitlike[01100011]>>4 result is [00000110] [10010101]>>4 The result is[11111001]//Red 1 is the most significant bitNoteFor u

Here is a top-level and cutting-edge Colloquium of computer systems held by EE Dept. Of Stanford Univ. Bookmark this Website: http://www.stanford.edu/class/ee380/ Here are some links from it:1.BRam Cohen, BitTorrent Http://stanford-online.stanford.edu/courses/ee380/050216-ee380-100.asxThis is a video talked by Bram Cohen (creator of BitTorrent) which focusing on what the interesting problems in studying Bi

. storage network DAS, NAS, SANDAS (direct attached Storage): direct-attached storage with a storage device that is tightly connected to the host.nas (Network Attachedstorage): Networked storage, file-based protocol, shared files over LAN, such as NFS,FTP, SMB san (Storage area Networks): Network region storage, the use of high-speed fiber-optic network to connect servers and storage devices, based on IP and other advanced protocols to achieve file sharing. linux Intro