performance tuning books

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 implementation of join. And this operation plays a crucial role in the secondary sort mode. Secondary sort mode refers to the user expects data to be grouped by key and wants to traverse value in a specific order. UserepartitionandsortwithinpartitionsPlus a part of the user's extra work can achieve secondary sort.ConclusionYou should now have a good understanding of all the essential elements needed to complete an efficient Spark program. In part II, you will learn more about resource invoc

Javascript's performance tuning point A, use caution to remember that the "eval" code is 100 times times slower than the "eval" code. The main reasons are: JavaScript code performs a "precompiled" operation before execution: first, it creates an active object in the current execution environment and sets those variables declared with Var to the properties of the active object, but at this point the variabl

|| Slow_launch_time | 2 |+------------------+-------+Mysql> show global status like '%slow% ';+---------------------+-------+| variable_name | Value |+---------------------+-------+| Slow_launch_threads | 0 || slow_queries | 4148 |+---------------------+-------+The configuration of the record slow query, the execution time of more than 2 seconds is slow query, the system shows that there are 4,148 slow query, you can analyze the slow query log, find the problem of SQL statements, slow query tim

, where sending data accounts for 99% of the time. Still more than the initial page load time. Finally, instead of innerjoin the table with the select method to remove the relevant data, leftjoin the table data, by looping the select result set, the data is obtained separately. After the modified development environment page load time is 0.2~0.3s, the server environment is 0.4~0.5s. Although not ideal, performance is acceptable for small systems withi

TraceView and androidtraceview of Android Performance Tuning Tool Since the 16 Performance Optimization series Videos released by Google in January, many excellent articles on the optimization series have been found in major communities during this time. I have analyzed the causes of performance, shared how to optimize

There are fewer tutorials on iOS performance tuning, and the decision to write an iOS performance Tuning series focuses on several aspects of memory leaks, performance optimization, traffic, and power analysis.Xcode has provided a very powerful

:1476275679681nofinalstr end:1476275680246volatilefinalstr begin:1476275680246volatilefinalstr end:1476275680642Finalchar begin:1476275680642Finalchar end:1476275680673Nofinalchar begin:1476275680673Nofinalchar end:1476275680735Volatilefinalchar begin:1476275680735Volatilefinalchar end:1476275680775String is 5-6 times slower relative to char and integer.Final in addition to objects, the native type can achieve the effect of a/C + + macro at compile time, so it is much better to be able to use na

Points:1. Purpose of memory optimization and introduction of tools2. Analysis and summary of the main problems of Android APP memory3. UI drawing principles and quantification tools-the main problems of UI fluency and the principle of UI drawing.4. How to get the UI smoothness of your app5. Impact of IO on application performance----------------------------------------------Project Code:----------------------------------------------1. Purpose of memor

1. Performance monitoringMode 1:/usr/local/tomcat7/conf/tomcat-users.xml Add the following:role rolename="Manager-gui"/> role rolename="Manager-script"/> role rolename="manager-jmx"/> role rolename="Manager-status"/> user username="admin" password= "admin" roles=" Manager-gui "/> user username="tomcat" password="Tomcat" roles ="Manager-gui,manager-script,manager-jmx,manager-status"/>Mode 2: Modify the/usr/local/tomcat7/bin/catalina.sh fi

jvmwa6460-2080816_22093 (JIT enabled, AOT enabled)J9vm-20080816_022093_ledsmrJit-r9_20080721_1330ifx2GC-20080724_AA)Jcl-20080808_02D:\Program FILES\IBM\WEBSPHERE\APPSERVER\JAVA\BIN>CD. /..D:\Program Files\ibm\websphere\appserver>cd BinD:\Program files\ibm\websphere\appserver\bin>serverstatus.bat-all//was deployed server stateadmu0116i: File D:\ProgramFiles\ibm\websphere\appserver\profiles\appsrv01\logs\serverstatus.loRecording tool information inadmu0128i: Starting a tool with a APPSRV01 profil

need to focus on and learn in IOS7, and then explore the chapters of their own interest. Plan to inherit the form of notes similar to WWDC2012 and hope that the domestic developers will be helpful.At lastOf course there are some other minor changes, including the addition of the attachment button in the Messageui, Xcode started to support the module, and so on. A complete list of iOS7 new features can be found here (for the time being, you should also need a developer account). The last good ne

for a while, so we went on the Performance Tuning journey of the Erlang network connection ~~ The process is really exciting. We soon passed the 1024 mark ~~ We were very excited when we reached 4999 connections. But why are there 4999 connections? Check the code and find that echo_server.erl defines a macro with the maximum number of connections being 5000 ~~After the compilation is modified, the number o

JVM Performance Analysis and Tuning 1) reasonably configure Parameters Jvm memory = heap memory + non-heap memory Heap memory = new generation + Old Generation = 1 Eden zone + 2 vivo VO zones Non-heap memory = persistent generation + code Cache -Server: server mode. This parameter is placed at the beginning of the configuration item. -Xms: the initial heap size. The unit is MB.-Xms is the same as-Xmx, whic

Mysql Tomcat C3p0 System Performance Tuning personal summary, System Information The application logic is to use c3p0 to query data in the database and return Json data over http. 1. the initial test result JMeter test result before optimization No. Type Original 1000 data bigger 1 500 Connection 250 query/S 63q/S70q/S 2 1000 connections 255q/S 57q/S65

15 useful MySQL/MariaDB performance tuning and Optimization Techniques MySQL is a powerful open-source Relational Database Management System (RDBMS ). It was released in 1995 (20 years ago ). It uses Structured Query Language (SQL), which may be the most popular choice in database content management. The latest MySQL version is 5.6.25, which was released on July 25, May 29, 2015. An interesting fact about M

, the most important of which is how long the thread has been running. Consider this factor to allow each thread to get the chance to run. So, regardless of how low the priority of the thread is set, they always get the chance to run.In addition, the weight of the thread priority set on the different OS is different. On Unix-based systems, the execution time of a thread is a factor in the current priority of the dominant thread, which means that the thread priority set is rarely "referenced". On

set-up value. The goal is to mitigate the effects of excessive procedures and therefore not buildDisable these settings globally. There is one more thing to note about Max_execution_time: It represents the CPU time of the process, not the absolute time. So a progressiveA program that runs large amounts of I/O and a small number of computations may run far more than Max_execution_time. This is also max_input_time can be greater thanThe reason for Max_execution_time.The number of log records that

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:

One, summing up the study of the day before From the "Third Day" performance Test section, we learned several important metrics for the deterministic test: • throughput Üresponsetime Ücpuload Ümemoryusage We have also done a certain optimization on the third day of study in Apache, to optimize the above 4 key readings, then our Apache tuning, our tomcat also make some corresponding adjustments, when t