cassandra tuning

Common SQL Tuning Tips and SQL Tuning tuningtips Create an appropriate index (refer to correct database index creation) Replace OR with UNION (applicable to index columns) Replace in and not in with exist and not exist Do not declare numbers in character format (this will invalidate the index and generate a full table scan) Do not use select * (list each column after select)

JVM tuning summary, jvm Tuning Auxiliary InformationJVM provides a large number of command line parameters and prints information for debugging. There are mainly the following: -XX: + PrintGCOutput Format: [GC 118250 K-> 113543 K (130112 K), 0.0094143 secs][Full GC 121376 K-> 10414 K (130112 K), 0.0650971 secs] -XX: + PrintGCDetailsOutput Format: [GC [DefNew: 8614 K-> 781 K (9088 K), 0.0123035 secs] 1

Oracle tuning uses related SQL, oracle tuning related SQL Select * from v $ session where username is not null;Select username, count (username) from v $ session where username is not null group by username;Select count (*) from v $ process;Select value from v $ parameter where name = 'processs ';Select count (*) from v $ session where status = 'active ';Select name, VALUE, DISPLAY_VALUE from v $ parameter

with a graphical performance detection tool. Ability to monitor memory, threads, class loading, virtual machine information, and moreVisual VM is a multi-in-one graphical performance detection tool that integrates a variety of new capability detection tools. Can replace some of the JDK's own tools, if JSTATE,JPS, etc.The Mat full name Memory Analyzer is a powerful Java heap analysis tool capable of analyzing heap memory leaks and viewing memory usage information.The Jprofiler tool is a powerful

Database Tuning tutorial (4) Explain performance analysis command, tuning explain In the previous chapter, we learned how to find slow queries and record statements into logs. How can we know where statement problems occur after slow queries are found. This chapter describes how to use the database performance analysis commands provided by Mysql to analyze SQL statements. Ii. Explain commands for database

Jvm-related parameters, tuning, and jvm parameter tuning Common jvm parameters are as follows: -Xmx1024m: Set the JVM maximum available memory to 1024 MB.-Xms1024m: Set JVM to enable the memory to be 1024 MB. This value can be set to the same as-Xmx to avoid JVM re-allocating memory after each garbage collection.-Xmn512m: Set the young generation size to 512 m. Memory size of the entire JVM = size of the yo

Meizu mobile browser compatibility tuning best practices, compatibility tuning Best PracticesProblem 1: Non-position: absolute container height: 100% does not take effect, leading to bottom location dislocation 1: The actual height of the container is rendered as 0. 2: Node 1 style contains position: relative; height: 100%; but the height in meizu mobile browser is rendered as 0Node 2 defines bot

Total – Age 3: 6817176 bytes, 18476608 all -age 4: 36258736 bytes, 54735344 total: 899459k->74786k (943744K), 0.0654030 secs] 1225769k-> 401096K (2504320K), 0.0657530 secs] [times:user=0.55 sys=0.00, real=0.07 secs]CMS Tuning The CMS collector needs more memory and allocates as much as possible. Reduce fragmentation and avoid full GC -xx:cmsinitiatingoccupancyfraction=n n is typically set to 75-80 (too early to start

Performance Tuning: IO consumption analysis, performance tuning io consumption Performance Tuning-> how to analyze io consumption Reprinted please indicate the source: http://blog.csdn.net/supera_li/article/details/45225077For more information about the performance tuning series, see.Performance Optimization: Analysis

Tags: style c tar ext a intHow to use Oracle's Dbms_sqltune package to run SQL Tuning Advisor for SQL automatic tuning1 ". Here's a simple example of how dbms_sqltune is used.First execute the next SQL that you want to tune, and then get the SqlidSql> SELECT * from V$sqltext where sql_text like ' select * from dual% ';ADDRESS hash_value sql_id command_type PIECE sql_text---------------- ---------- ------------- ------------ ---------- ----------------

Http://www.360doc.com/content/14/1208/13/16070877_431273418.shtmlUse JMeter to stress test tomcat and Tomcat performance tuningNginxtomcat Throughput Research ReportHttp://wenku.baidu.com/link?url= Fmp1sd8qbi87s23kei5nbek7mpjr-mwbte-pb4bn4iyqn1vqoagkig7bbnn5csmryhye4skxyoc5emjukc1gwqxnbgxsvrthadaxbcannf3Http://www.open-open.com/lib/view/open1401931407228.htmlIntroduction to JMeter's articlesHttp://www.cnblogs.com/TankXiao/p/4045439.htmlView JMeter Aggregation Tree ResultsTuning Series-tomcat

FineReport performance tuning methods, finereport Performance TuningThe basic idea of FineReport performance optimization is to properly set the memory size of the application server. Generally, the default memory configuration of the server is relatively small. In larger application projects, this memory is not enough. Therefore, you need to increase the memory size during processing. The memory configuration methods for each application server are d

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

Linux memory basic knowledge and related tuning solutions, linux TuningMemory is one of the important components in the computer and serves as a bridge to communicate with the CPU. All programs in the computer run in the memory, so the memory performance has a great impact on the computer. Memory is used to temporarily store computing data in the CPU and data exchanged with external memory such as the hard disk. As long as the computer is running, the

Sysctl. conf for learning and tuning, and sysctl. conf for tuning Reproduced in the short book: sysctl. conf learning and tuning. If you have any version problems, please contact mePreface Remember the first contact/etc/security/limits.confAnd/etc/sysctl.confThis is because kernel parameters must be modified as needed during Oracle deployment. The limits. conf fi

MYSQL Enterprise common architecture and tuning experience sharing, mysql tuning Experience Sharing 1. Select Percona Server, MariaDB or MYSQL Mysql application source: http://www.jinhusns.com/Products/Download? Type = xcj 1. Three storage engines of Mysql MySQL provides two storage engines: MyISAM and InnoDB, MySQL4 and 5 using the default MyISAM storage engine. From MYSQL5.5, MySQL has changed the defaul

The individual believes that JVM tuning is primarily addressed by the following methods1. Set the appropriate maximum heap memory (maximum and value for Cenozoic and Laosheng generations) and minimum heap memory (the operating system memory size consumed by JVM startup), and set the scale allocation of the heap.2, set up the suitable new generation because of its impact on the system performance and GC recovery has a certain effect.3. Set the appropri

MySQL performance tuning and Architecture Design-the idea and solution of the High Availability design in Chapter 17th, mysql Tuning Chapter 1 High Availability design ideas and solutions Preface: The database system is the core part of an application system. To ensure the overall availability of the system, the database system cannot have any problems. For an enterprise-level system, the availability of th

Optimized tuning of TCP/IP and kernel parametersThere are many ways to optimize TCP/IP and kernel parameters under Linux, the configuration of parameters can greatly improve the performance of the system, and can also be optimized according to specific scenarios, such as time_wait, DDoS attacks and so on.The following configuration is written in sysctl.conf and can be used with sysctl-p.The relevant parameters are for reference only, the specific valu

Tags: sdn is ola visible reason water personal tuning tunToday, while watching Tri Hua's SQL optimization book, he saw a case in which he solved the SQL performance problem, and Tri Hua the teacher successfully positioned the problem and solved it. Here, on the basis of Tri Hua teacher analysis and positioning, do further analysis and reasoning, so that we can study and discuss together, the following is a brief description of the case scenario. 1. SQ