[Architecture problem solving: 1] solution to 4031 errors: Architecture 4031

[Architecture problem solving: 1] solution to 4031 errors: Architecture 4031
III. solution 4031 error method :( ora-4031 error cause: a large number of hard parsing, resulting in chain chunk are changed very small, at this time a large SQL will not find the appropriate chunk, the ora-4031 error will be reported .)
If SHARED_POOL_SIZE is set to large enough and the Bug can be ruled out, most ORA-04031 errors are caused by excessive memory fragments caused by a large number of SQL code in the shared pool.
1. Execute alter system flush shared_pool; clear library cache and rows cache. This method can only temporarily solve the problem and is not recommended. Cause: (1) Flush Shared Pool will cause unused cursor to be cleared out of the Shared Pool. If these SQL statements need to be executed subsequently, the database will experience a lot of hard parsing, the system will experience severe CPU contention, and the database will have intense L atch competition. (2) If the application does not use Bound variables and a large number of SQL statements are not executed, Flush Shared Pool may only provide a short improvement and the database will return to the original state soon. (3) If the Shared Poo l is large and the system is very busy, refreshing the Shared Pool may cause the system to be suspended. For similar systems, try to do so when the system is idle.
2. method 2: allow developers to modify SQL statements to share SQL statements. 3. method 3: save large objects to the memory. method 4: Set the shared_pool_reserved_size parameter and use the shared_pool_reserved_min_alloc parameter to avoid performance degradation. The default value of this parameter is 5% of shared_pool_size. The recommended value of this parameter is 10% ~ of shared_pool_size ~ The size of 20%. The maximum value cannot exceed 50% of shared_pool_size. The reserved area is used to cache large object areas in the shared_pool, so the size of the reserved area can be increased. # View the number of errors in the request retained area. (If the request retained area is incorrect, the packet will contain an error 4031.) select REQUEST_MISSES from v $ shared_pool_reserved; 6. use AMM Automatic Memory Management to allocate a shared pool to prevent small and incorrect sharing pool settings. (This step is generally done)
What are the problems solved by the computer architecture course? And the solution?

ComputerArchitecture is the attribute of the computer that programmers see, that is, the conceptual structure and functional characteristics. According to the multi-level hierarchy of the computer system, the computers seen by programmers of different levels have different attributes. In general, the properties of low-level machines are basically transparent to high-level machine programmers. Generally, the computer architecture mainly refers to the system structure of machine language-level machines. The classic definition of "computer architecture" is 1964 C. m. amdahl introduced the IBM360 system and described it as "the computer architecture is the properties of the computer that programmers see, that is, the conceptual structure and functional characteristics"

Basic Concepts
A computer architecture refers to a collection of system elements that are properly organized together. These system elements work together and collaborate with each other to achieve predefined goals through information processing. The system elements include: computer software, computer hardware, personnel, databases, documents, and processes. Among them, software is a collection of programs, data structures and relevant documents, used to implement the required logical methods, processes or control; hardware is an electronic device that provides computing power and an electronic mechanical device that provides functions in the external world (such as sensors, motors, pumps, etc.); personnel are users and operators of hardware and software; A database is a large, organized collection of information accessed through software. A document describes the manuals, tables, images, and other descriptive information about the use of the system. A process is a series of steps, they define the specific usage of each system element or the procedural context in which the system resides. Computer Architecture
Eight attributes
1. On-premises Data Representation: Data Types and formats that can be directly recognized and operated by hardware. Computer Architecture
2 • Addressing Mode: Minimum addressable unit, addressing type, address operation 3 • Register Organization: definition, quantity, and usage rules of operation registers, address change registers, control registers, and special registers 4 • Command System: operation Type, format, sorting and Control Mechanism of machine commands 5 • Storage System: Minimum addressing unit, addressing method, primary storage capacity, maximum addressable space 6 • interrupted organization: 7. Input/output structure: connection Mode of input/output, data exchange mode between processor/memory and input/output device, and control of data exchange process 8 • Information Protection: information protection mode and hardware information protection mechanism.
Edit the development history of this section
Computer systems have gone through four different stages of development. Computer Architecture
Stage 1
Before the middle of 1960s, it was an early era of computer system development. In this period, general hardware has been quite common, but software is specially written for every specific application. Most people think that software development requires no prior planning. At this time, the software is actually a small program, and the program writers and users are often the same (or the same group) people. Because of its small scale, the program is quite easy to write and there is no systematic way to manage software development. This individualized software environment makes software design a fuzzy process hidden in people's minds. In addition to the program list, there is no other document to save.
Stage 2
From the middle of 1960s to the middle of 1970s, it was the second generation of computer system development. In the past 10 years, computer technology has made great progress. Multi-channel programs and multi-user systems introduce the new concept of human-computer interaction, create a new realm of computer applications, and bring a new level of cooperation between hardware and software. The real-time system can collect, analyze, and convert data from multiple sources of information, so that process control can be performed in milliseconds rather than minutes. The advancement of online storage technology has led to the emergence of the first generation of database management systems. An important feature of the second generation of computer system development is the emergence of "Software workshops", which are widely used in product software. However, software workshops still follow the Early individualized software development methods. With the increasing popularity of computer applications, the number of software has expanded dramatically. Errors found during the running of the program must be corrected. When users have new requirements, they must modify the program... the remaining full text>

How to solve computer architecture Problems

Direct ing first partitions by cache, 1024/64 = 16, 1000001100 =, 524,524/64 = 8 .. 12,
The address is located in 12th storage units in Zone 8 and in 0th rows.
Full join can be loaded at will, 524 mod 16 = 12, 12th storage units in this row