db2 sql performance tuning

executable query statements that are executed at the Master end, and executes the query itself. In this way, the same Query is actually executed on the Master and Slave ends, so the data on both ends is exactly the same.In fact, in the old version, the replication implementation of MySQL was done on the Slave side not by the two threads of the SQL thread and IO thread, but by a single thread to do all the work. But MySQL engineers quickly found that

database SELECT statement printed from the log of the program) after the SELECT statement Jmeter testresult No. Type Original Bigger 1 500Connection query/s CPU 100%150q/s 2 Connections 255q/s 160q/s160q/s The problem now is that the Tomcat request 160q/s no more tuning, Tomcat's memory configuration 4G actually used less than 1 G, CPU 8 core utiliza

of disk sorting will be greatly increased. This is mainly because at the end of the month, users will make statistics on the transaction data for the month. So at the beginning of the month, because of the number of transactions, so there will be more disk sorting occurs. In this case, it is necessary for the database administrator to adjust the relevant parameters. However, this adjustment is a temporary adjustment, until the cycle has passed, still need to transfer the parameters back. Only i

Io is very relevant, when the free buffer waiting in the v$session_wait of the entry is very small or not, Explain the DBWR process of your system will be enough, do not need to adjust, there are many items of free buffer wait, your system must feel very slow, then your DBWR is not enough, the resulting wio has become your database performance bottlenecks, the solution is as follows: A.1 to increase the write process while adjusting the db_block_lru_

(dl_expint) Dl_num_copies:No data link replica count (dl_num_copies)Dl_time_drop:The performance parameters of the IBM DB2 database do not have the data link time after the removal (dl_time_drop) Dl_token:Low Data Link token algorithm (dl_token) Dl_upper:No data link token in upper case (dl_upper) Dyn_query_mgmt:Low-dynamic SQL query Management (dyn_query_mgmt W

the importance of statistical information is self-evident. Interested children's shoes can be noticed in advance.The content of SQL Server performance tuning involves a wide range of topics, followed by an analysis in the following article.If you have any questions, you can leave a message or private messages, and look forward to an in-depth study of your child'

the deterioration of performance is a variety of factors, and sometimes the results of the performance degradation caused by multiple elements, this requires the database administrator has a more comprehensive computer knowledge, can be sensitive to the impact of the database performance of the main reason. In addition, good database management tools are also im

ObjectiveAfter the analysis of the previous few, in fact, in general has been the first glimpse of the importance of SQL Server statistics, so this article will be sacrificed this artifact.This content will be very long, sit good bench, melon seeds snacks and so on ...No nonsense, go to the chase.Technical preparationThe database version is SQL SERVER2008R2, which is analyzed using Microsoft's previous case

Method One: Caching data in the Init () method of the Servlet After the application server initializes the servlet instance, it invokes the Init () method of the servlet before servicing the client request. In the lifecycle of a servlet, the init () method is invoked only once. System performance can be greatly improved by caching some static data in the Init () method or by completing some time-consuming operations that need to be performed only onc

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

Program | index | performance You can use SQL Server adjuster (SQL Server Profiler) tools to collect important information about the current activity of the server. The information tracked by this profiler tool, which contains the real load of the database, can be used on a variety of occasions. Now let's look at how to use Profiler to collect the data that can b

Summary: This article begins with a detailed introduction to the concept of shared pool in Oracle and the memory structure included. It then provides an in-depth overview of Oracle's management mechanisms for shared pool. Finally, the paper introduces the practical method of buffer cache monitoring and tuning. 1. The concept of shared pool Oracle databases, as a product of managing data, must be able to recognize the administrative commands (often c

Source Address: https://msandbu.wordpress.com/2014/10/31/netscaler-and-real-performance-tuning/The author is obviously not a native English speaker, so some places I look at is also more laborious, but very grateful to the original author.========= translated content started =========Yesterday I had a meeting with Citrix User group in Norway on NetScaler and performance