elasticsearch query performance tuning

Tags: bottleneck affects LAN connectivity and so on addition query framework staticReprinted from Http://www.cnblogs.com/jiaosq/p/5843437.html Today, database operations are increasingly becoming a performance bottleneck for the entire application, which is especially noticeable for web applications. It's not just about the performance of the database that DBAs n

A, sub-tableHorizontal DivisionVertical DivisionSecond, read and write separationThird, choose a reasonable data type, especially the primary keyIv. files, pictures and other large files using file system storageFive, database parameter configurationNote: The maximum number of max_connections connections is usually set at around 1000 to 2000 to the limit.Query_cache_size Query Cache SizeSix, reasonable hardware resources and operating systemMySQL Data

to select the crosstab (intersection table) as the underlying table, which is the table referenced by the other table.Like what: The EMP table description describes the intersection of the location table and the category table. SELECT * FROM location L, CATEGORY C, EMP E WHERE e.emp_no between, and e.cat_no = C.cat _no and e.locn = L.LOCNwill be more efficient than the following SQL: SELECT * from EMP E, location L, CATEGORY C WHERE e.cat_no = c.cat_no and e.locn = L.

-------------------------------------------------------------------------| Id | Operation | Name | Cost (%CPU) |-------------------------------------------------------------------------| 0 | SELECT STATEMENT | | 4 (0) || 1 | TABLE ACCESS by GLOBAL INDEX rowid| SALES | 4 (0) || 2 | INDEX RANGE SCAN | Index_qu_sold | 3 (0) |-------------------------------------------------------------------------9 Rows selectedSql> alter session Set "_use_nosegment_indexes" =true;Session altered.Sql> CREATE index

Tags: performance optimization slow query MySQL database tuning databasefirst, find slow query The last thing we do is to prepare for the occurrence of slow queries, which allows us to find slow queries and record them in a file .. 3. Record Slow queries At this point we already have the cost of making the slow

, insufficient use of resources or the structure of the program is unreasonable.For Java applications, the method of looking for performance bottlenecks is typically to analyze resource consumption first, and then combine some Java tools to query for code that causes excessive resource consumption in the program. CPU Consumption AnalysisContext SwitchesEach CPU can execute only one thread at a time,andLinux

1, Tomcat's external tuningJava Virtual Machine (JVM) performance optimization allows you to set the size of the virtual machine using memory,-xmsThe size of these two values is generally set as needed. The size of the initialization heap performs the size of the memory that the virtual machine requests to the system at startup. Generally speaking, this parameter is not important. However, some applications in a large load of the case will be a sharp

Label:MySQL performance tuning and architecture design--1th chapter MySQL Basic introductionPreface:As one of the most popular open source database software, MySQL database software has been widely known. But in order to take care of the readers who are not familiar with MySQL, this chapter will make a brief introduction to MySQL. The main content includes MySQL each function module composition, each module

monitoring is necessary 207Thinking on the construction of 6.7 operation and maintenance platform--meta data management 2096.8 Monitoring blind spots and diagnostic cases 210Monitoring blind spots: A potential monitoring problem caused by dual 210Diagnostic Case: Standby CPU Usage Exception Optimization 213Diagnostic Case: Two alarm information combined with analysis of DG Problem 216Diagnostic case: Monitoring anti-monitoring error--an analysis of a Orabbix alarm 222Diagnostic case: Customizin

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

with group_message_bad in the sample code. P1943rd rowsOriginal article: "This will not only waste the memory of the Query Cache for frequently changing Table queries"->: "This not only avoids frequent Table queries from wasting the memory of the Query Cache" P196Last 1st rows:Original article: "first look at the performance configuration items connected to the

Client protocols Aliases The Protocol is the same as (2). You can specify more configurations. 3. sp_configure/reconfigure Displays or changes the global configuration settings of the current server. Many configurations need to be set through sp_configure. Syntax: sp_configure [ [ @configname = ] 'option_name' [ , [ @configvalue = ] 'value' ] ] reconfigure For example: To configure advanced options with sp_configure, you must first run sp_configure when the "show advanced options" op

;=@firstSensorID and Msl.id@lastSensorIDSelectCount (1) as[motioninferred] from[Tracks]. [dbo]. [Monitorsensorlog] MSLwhereMsl. Sensortype='motioninferred'and msl.id>=@firstSensorID and Msl.id@lastSensorID End View Code 4.Union VS Union AllUnion: Sets the two result sets, excluding duplicate rows, and sorting the default rules. Union All: Set operation on two result sets, containing duplicate rows, without sorting. INTERSECT: Is the intersection of two query