oracle performance tuning guide

be adjusted to improve the performance of the job immediately. We need to perform a comprehensive analysis of the spark job based on different business scenarios and data conditions, and then adjust and optimize it in many ways to get the best performance.Based on the previous experience of spark job development and the accumulation of practice, the author summarizes a set of performance optimization schem

, process properties, and resources for the build process. If you understand the process constructs, you can understand what is important for the running and performance of the process. Figure 1-2 shows an overview of process information related to process architecture.Linux process management for Linux Performance and Tuning

First, diagnostic tools 1. Warning Log file Warning log files contain system information and error logs that contain important errors (such as: ORA-600) and block checksum error messages (ora-1578,ora-1498). Monitor database operations such as CREATE DATABASE, STARTUP, SHUTDOWN, ARCHIVE log, and RECOVER, and record Non-default initialization parameter values. When Log_checkpionts_to_alert is set to true, the warning log file also records the start and end times of checkpoints, incomplete checkpo

The author of this book is a leader in Java performance and Java HotSpot virtual machines, helping you to use modern soft practices to improve your practical life by summarizing energy, avoiding common mistakes, and tips and tricks.Using G1 to overcome the limitations of parallel, serial, and CMS garbage collectors learn about the various stages of G1 GC collection, including the young generation and the old era fine

that will cause underlying performance problems. On the other hand, interacting with users may impede your work progress. Success also results in exposure of the next layer of performance problems. What do users cannot tell you? The bottom-up method of a user reveals that a single package consumes about 25% of the input and output resources. For another user, a single query may cause TB of buffer input and

virtual memory management of Linux, if a memory page has been allocated, but has not been used for a period of time, Linux will move the memory page into swap space.You can often see daemons such as Getty, which are usually started when the system is started, but are rarely used. It seems more efficient to free up the precious main memory of the page and move it to the swap area. This is how Linux manages swap, so you don't need to panic when you find that the swap area is already using 50%. Th

execution time of full GC. The goal is to minor GC time within 100MS and full gc time within 1s. Main tuning Parameters:Set the heap memory size, which is the most basic. -XMS: Heap memory space When the JVM is started. -XMX: Maximum heap memory limit. Sets the Cenozoic size.The new generation should not be too small, otherwise there will be a large number of objects pouring into the old age. -xx:newratio: The proporti

advantage of this algorithm is to increase the scalability of the Linux kernel for enterprise-class environments with a large number of threads and processes and multi-processors. The new CPU Scheduler for O (1) was designed for memory 2.6, but has now been ported to the 2.4 series. Figure 1-8 illustrates how the Linux CPU is scheduled to work.Figure 1-8 Linux Kernel 2.6 O (1) SchedulerAnother notable improvement to the new scheduler is the support for non-conforming Memory Architecture (NUMA)

Label:Poptest is the only training institute for developing Test and development engineers in China, aiming at the ability of the trainees to be competent in automated testing, performance testing and testing tools development. If you are interested in the course, please consult qq:908821478, call 010-84505200. 1 Overview of Performance optimizationsThis chapter provides an introduction Toperformance

settimeoutc) Use canvas animations appropriately, use CSS animations within 5 elements, and more than 5 using canvas animations (iOS8 can use WebGL)· High Frequency event OptimizationTouchmove, Scroll events can cause multiple renderingsA) use Requestanimationframe to monitor frame changes to make rendering at the right timeb) Increase the time interval for response changes and reduce redraw times· GPU AccelerationThe following properties in CSS (CSS3 transitions, CSS3 3D transforms, Opacity, C

the node is overloaded and requests load balancing.Figure 1-9 O (1) CPU Scheduler structureTranslator Note: In the process of translation, deeply feel that process scheduling is a very complex task. If you want to learn more about the 2.6 kernel process scheduling also need to review the relevant information, here are some about the 2.6 kernel process scheduling articles, interested friends may wish to see.Linux 2.6 Scheduling System Analysis: http://www.ibm.com/developerworks/cn/linux/kernel/l

using jquery chain operations. As shown below: Copy Code code as follows: var $active _light = $ ("#traffic_light Input.on"); $active _light.bind ("click", Function () {...}) . CSS ("Border", "1px dashed yellow") . CSS ("Background-color", "orange") . FadeIn ("slow"); If you intend to use jquery objects in other functions, you must cache them in the global environment. As shown in the following code: Copy Code code as follows:

so on, are suitable for this technology. 7, compressed JavaScript Compress and minimize your JavaScript files. Online compression address: http://dean.edwards.name/packer/ Before compressing, please ensure that your code is normative, otherwise it may fail, resulting in a JS error. jquery Performance Tuning

, Oracle will rearrange the NON-ACCESS predicate order to reduce CPU costs, but in most cases it will not be aware of performance differences.) ） Overall-it ' s definitely a good thing. In practice, you may have a much stronger bias towards indexed access paths which the May impact performance. Anyway--it's certainly a good thing. In fact, you can find a stronge

. MongosniffThis tool can monitor from the bottom to what commands are sent to MongoDB for execution, from which it can be analyzed: EXECUTE as root: $./mongosniff--source NET Lo It then monitors all packet requests to local mongodb with localhost listening on the default 27017 port.2.MongostatThis tool provides a quick view of the statistics field descriptions for a set of running MongoDB instances: Insert: Insertion amount per second Query: Number of queries per second Update

jQuery1.3.1 version, and the function of this method is to dynamically bind events to the new DOM elements.But for efficiency, this method is more resource-intensive. So please try not to use it.Original codeAfter running, you will find the new P element and no use being bound by the Click event.You can change to. Live ("click") to resolve this issue, the code is as follows:New Code$ (function () {$ ("P"). Live ("Click", Function () {///change to Live modeAlert (This). text ());});$ ("button").

cause mobile phone over-consumption increased.HTML5 is just a method and means, and not omnipotent, thinking how to meet the mobile device in particular yes, but the premise must be based on the PC station frame structure and content, to ensure that the consistency of the content is the only way to solve the HTML5 pain point, this time everyone to understand "what is suitable for mobile display site" is not to stand at the high point to understand, should stand at the lowest point, how to displ

problems.Because the paging mechanism cannot handle requests for physical memory pages, the swap mechanism will invoke more free memory pages.This drastically increases the I/O to the disk and quickly pulls down the performance of the serverIf Your server is always paging to disk (A-page-out rate), consider adding more memory.However, for systems with a low page-out rate, it might not affect performance.If the server is always changing pages (a very

Over the past decade, Oracle has become one of the most professional databases in the world. For IT professionals, it is important to ensure that Oracle's powerful features are used to improve the productivity of their companies. One of the most effective ways to do this is through Oracle tuning. It has a large number of tuni