elasticsearch query performance tuning

MySql performance tuning policy and mysql tuning policy This topic provides detailed parameter descriptions for my. cnf configuration. The sample configuration is as follows: # Cat my. cnf # MySQL client library initialization. [Client] Port = 3306 Socket =/tmp/mysql. sock Character-set-server = utf8 # The MySQL server [Mysqld] Init_connect = 'set na

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

Performance optimization is to improve the system performance, reduce energy usage, or reduce the impact of applications on other parts. If the optimization is hasty or there is no measurement, of course, performance optimization may have a bad effect. Performance optimization is to improve the system

other is that we have not achieved our expected goal. We need to find performance bottlenecks and optimize the performance. 3. Performance Analysis Through the above performance test, we found that the website did not meet our expected performance goal. What we need to do i

Cache Size| Query_cache_type | On | cache type, determines what queries are cached| Query_cache_wlock_invalidate | OFF | when other clients are writing to the MyISAM table If the query cache is returned , the cache result, or wait for the write operation to complete the reread table to get results+------------------------------+---------+Mysql> show global Status Like "qcache%";+-------------------------+-------+| va

test, we found that the website did not meet our expected performance goal. what we need to do is to monitor the existing system (server), including hardware and software monitoring, it provides effective performance monitoring data for performance tuning. Next we will focus on what tools can be used to identify

can avoid Key lookup is perfect, let's revise non-clustered index to include it in the index with the Include keyword His fields are:[SQL] DROP INDEX idx_non_clust_salesorddetaildemo_modifieddate on salesorddetaildemo GO CREATE nonclustered INDEX idx_non_clust_salesorddetaildemo_modifieddate on salesorddetaildemo (ModifiedDate) INCLUDE ( ProductID, UnitPrice ) GO --Clear the cache, only for the development environment! DBCC Freeproccache DBCC dropcleanbuffers GO

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

MySQL performance tuning and Architecture design--9th chapter The performance optimization of MySQL database schema designPreface: Many people think that performance is optimized in the process of writing code (program code or database code), in fact, this is a very big misunderstanding. The real impact of the most

caches.As shown, when we open the query cache, the actual run time is reduced by 40%, although memory usage does not change significantly.There are three types of cache options available, set by Query_cache_type control. Setting a value of 0 or off disables caching Setting a value of 1 or on caches all selections except the beginning of the Select Sql_no_cache Setting a value of 2 or DEMAND only caches selections beginning with selec

monitoring, it facilitates Performance Optimization after the product is launched.The other is that we have not achieved our expected goal. We need to find performance bottlenecks and optimize the performance.#3. Performance analysis ##Through the above performance test, we

range. That doesn't make sense either. For performance testing, we also need to define a time period. For example, it lasts 15 minutes on a certain throughput. Because the system becomes unstable when the load arrives, the system will stabilize after a two-minute time. In addition, it is possible that your system behaves normally in the first few minutes of the load, and then it is unstable and even collapsed. So it takes so long. This value, we

Performance bottlenecks:Slow, write faster than read The main performance indicators:Frequency of visits,The number of concurrent connections,Cache Hit Ratio,Index use,Slow log opening and analysis,Query log, querying logThreads_cached: Whether the connection thread cache is turned onThread_cache_size: The size of the number of thread cachesQuery_cache_size:

Pq_distribute hints are often used to improve the performance of connection operations between partitioned tables in the Data Warehouse. The Pq_distribute hint allows you to determine how table data rows participating in a connection are allocated between production and consumption parallel query service processes. Pq_distribute prompt accepts three parameters: table name, outer allocation, and internal all

JavaScript is a relatively complete front-end development language, in today's web development applications are very wide, especially for Web 2.0 applications. As Web 2.0 becomes more and more popular today, we will find that there will be a lot of JavaScript code in our Web application projects, and that there will be more and more in the future. JavaScript, as a language to interpret execution, and its single-threaded mechanism, determines that performance