postgresql performance tuning parameters

the heap is large in size, complete garbage collection can be slow, but the frequency is reduced. If you match the size of the heap with the need for memory, the collection will be complete quickly, but will be more frequent. The purpose of the heap sizing is to minimize the time spent in garbage collection to maximize the processing of customer requests for a specific period of time. In the benchmark, to ensure the best performance, the heap size is

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

. 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

Document directory Configuration Optimization Because the performance tuning section of the official book does not index by configuration item, quick query cannot be achieved. So I re-organized the original text with the configuration item drive and added some of my own understandings. If there is any error, please correct me.Configuration Optimization Zookeeper. session. Timeout Default Value:3 minute

to 10% of the memory size of each executor; and then we usually project, when we actually handle big data, There will be problems here, causing the spark job to crash repeatedly and not run, and then adjust this parameter to at least 1G (1024M), Even say 2G, 4G Usually this parameter is adjusted up, will avoid some JVM oom abnormal problem, at the same time, will let the whole spark job performance, Get a bigger boost. Adjust wait time long .

);} /// ///generate time information from the GUID returned by SQL SERVER/// /// comb that contain time information/// Time Public Staticdatetime getdatefromcomb (System.Guid Guid) {datetime basedate=NewDateTime (1900,1,1); byte[] Daysarray =New byte[4]; byte[] Msecsarray =New byte[4]; byte[] Guidarray =GUID. Tobytearray (); //Copy The date parts of the GUID to the respective byte arrays.Array.copy (Guidarray, Guidarray.length-6, Daysarray,2,2); Array.copy (Guidarray, Guidarray.length-4, Ms

Performance test of Nginx performance tuningCourse View Address: HTTP://WWW.XUETUWUYOU.COM/COURSE/38Courses from the School of worry-free network : http://www.xuetuwuyou.com/The course starts with the introduction of Nginx, including Nginx installation, configuration, monitoring, tuning all aspects of excellence, can be a comprehensive learning nginx.Lesson 1:ngi

Recently, the following project encountered an urgent problem, my old horse and young people to fight together. The problem is that many queries are incredibly slow when the pressure data is poured into the database. Said there must be some basic guidelines for performance issues. The order of performance problems tunning 1 Architecture design (software architecture and database design, poor design is alm

Debug Resource AllocationThe Spark's user mailing list often appears "I have a 500-node cluster, why but my app only has two tasks at a time", and since spark controls the number of parameters used by the resource, these issues should not occur. But in this chapter, you will learn to squeeze out every resource of your cluster. The recommended configuration will vary depending on the cluster management system (yarn, Mesos, Spark Standalone), and we wil

dbms_spd.flush_sql_plan_directive;SET Linesize 200COLUMN dir_id FORMAT A20COLUMN owner FORMAT A10COLUMN object_name FORMAT A10COLUMN col_name FORMAT A10SELECT To_char (d.directive_id) dir_id, O.owner, O.object_name,O.subobject_name Col_name,o.object_type, D.type, D.state, D.reasonFrom Dba_sql_plan_directives d,dba_sql_plan_dir_objects oWHERE d.directive_id=o.directive_idand O.owner = ' TEST 'ORDER by 1,2,3,4,5;No rows selectedSql>2. Performance feedb

Transferred from: http://blog.csdn.net/defonds/article/details/6289236If you feel your eclipse is slow, you can adjust it by modifying the%eclipse_home%/eclipse.ini file:Adjust the memory of-XMS and-xmx to 512m (512m if your native memory is 1/4,2g):-xms512m-xmx512mThen add the following line parameters at the end of the file: -xx:permsize=96m-xx:maxpermsize=96m-xmn168m-xx:+disableexplicitgcThe speed has improved significantly after the configuration

] mysqldump [Options]--databases [options] DB1 [DB2 DB3] ... mysqldump [Options]--all-databases [options] 1 "MyISAM engine, can directly copy data sheet. 2 "mysqldump: Data export to SQL statement 3 "SELECT * FROM table1 to outfile '/tmp/table1.txt '; 4 "Recovery: Load Data infile '/tmp/table1.txt ' into table table1; 4,mysqlimport Mysqlimport [OPTIONS] Database textfile ... The Mysqlimport program is a tool program that will store text data in a specific format (such as data files generated

Ceph performance tuning-Journal and tcmalloc Recently, a simple performance test has been conducted on Ceph, and it is found that the performance of Journal and the version of tcmalloc have a great impact on the performance.Test Results # rados -p tmppool -b 4096 bench 120 write -t 32 --run-name test1 Object

configuration. Linux is rich, powerful, and flexible, and you can do a variety of tasks with it, and in this article we'll discuss some tips for improving the performance of Linux servers.1. Tuning the Linux kernel elevator algorithm for disk I/OAfter selecting the file system, there are some kernel and mount options that may affect its performance, one of which

The effect is, with 2/8 principles, M.F.B. s to solve most things. So kick, limited to the overall adjustment, not involved in specific details.1, InnoDBUsing the InnoDB engine2, Innodb_buffer_poolAdjust and innodb about the parameters, as much as possible in memory and InnoDB instance3. IndexIndex, needless to say.4. CacheQuery caching, such as Redis5. Batch Writesuch as queue cache data, there is a dedicated thread in the idle batch storage6, SQL ca

Student Information Maintenance page for basic systems , Query displays student information , but each query process is slow , so the optimization of this part .Hibernate tuning is using SSH The framework is a common problem , generally can be considered from the following aspects :I. Database design and adjustmentSecond, the main configuration parameters ( ID build policy, Level two cache, Lazy load)三、一级 C

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 network and their impact on performance"->: "

Hive General learners and trainers in the performance optimization of the general will be from the syntax and parameters of these tricks point of view, but not revolutionary optimization of hive performance, the reasons for this phenomenon are: 1, historical reasons and stereotypes: When you learn SQL is generally a stand-alone db, this time your

recommended to copy the library file tcnative-1.dll to the bin directory of Tomcat. In linux, you can directly decompress and install the tomcat_native.tar.gz file under the bindirectory. Before compiling, make sure that the APR library has been installed.How can I determine whether the APR library is enabled for Tomcat? The method is to view the Tomcat startup log:If APR is not enabled, the startup log generally contains the following:Org. Apache. Coyote. http11.http11protocol startIf APR is e

the optimal number of threads" ) b. Increasing the cache C. Where the insert operation is performed frequently, bulk insert with native SQL (persistence layer using Eclipselink)2. Parameter adjustment A.JVM memory parameters B. Database connection pool parameters3. The function realizes the design adjustment (least wants to see)According to the actual situation to adopt appropriate means adjustment.Step ThreeDetect the