postgresql performance tuning parameters

performance, or data security, whether it's a local disk or a networked storage device, whether you want an exception to be resolved automatically, or if you want manual control, you can do so with a simple configuration file.Of course, the rich configuration brings great flexibility, but also requires the user to have enough knowledge of it, otherwise it is difficult to decide how to configure in so many configuration

in the document describe this value as a percentage of the total memory that represents the maximum amount of cache dirty data. In fact, view the description of the source code, its true meaning is accounted for (Percentage of Memfree + cached-mapped). When this limit is reached, Pdflush will wake up to flush the dirty data to disk, and all write Io will be blocked before the dirty data is entered into the disk. So if this value is too large, a write IO peak will occur for the period, and the p

, (Shell loop): [[Email Protected]_slave1~]# forRichyinch' Chkconfig--list |grep"3:on"|awk'{print $}'|grep-ve"Crond|network|sshd|rsyslog|sysstat"`; Dochkconfig $richy off;d one[[email protected]_slave1~]# chkconfig--list |grep"3:on"Crond0: Off1: Off2: On3: On4: On5: On6: Offnetwork0: Off1: Off2: On3: On4: On5: On6: Offrsyslog0: Off1: Off2: On3: On4: On5: On6: Offsshd0: Off1: Off2: On3: On4: On5: On6: Offsysstat0: Off1: On2: On3: On4: On5: On6: Off4. Close Iptables FirewallIn the daily work, gene

Before doing stress testing in a customer, the performance is not going to go, later adjusted the network parameters of AIX performance improved.The records are as follows:OS (AIX): Requires root access/usr/sbin/no-p-O tcp_sendspace=4194304/usr/sbin/no-p-O tcp_recvspace=4194304/usr/sbin/no-p-O rfc1323=1/usr/sbin/no-p-O sb_max=8388608Results can be set by no–l che

multiple frames. B. Polling: Process queue is processed with timed interrupts. B. The drive will automatically adjust the interrupt handling under high load. C. Summary: A. Reduce CPU service time and utilization.B. Increase the receive buffer by some C. When the load is low, increase the delay. D. Different strategies are used to adjust throughput based on different characteristics of the packet.13.12 Tuning Interrupt handlingAdjust interrupt handli

different application load requirements, it provides many adjustable system parameters. The main parameters related to performance tuning include: (1) Global Cache-Size; default value: 32 MB (2) Write-Cache-Size for each file. The default value is 1 MB. (3) number of I/O concurrency. The default value is 16. (4) Read-

Jvm-related parameters, 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 J

Guide Performance tuning has always been one of the most important work of operations engineers, if you are in a production environment encountered a slow system response, hard disk IO throughput anomalies, data processing speed is lower than expected, or such as CPU, memory, hard disk, network and other system resources have been exhausted for a long time, Then this article will really help you, if no

Recently, due to Project Memory leakage, large-scale JVM performance tuning has been performed. , Now we will record the experience. I. JVM Memory Model and garbage collection Algorithm 1. According to the Java Virtual Machine specification, JVM divides the memory: New (young generation) Tenured (elder generation) Permanent generation (Perm) Among them, new and tenured are heap memory. The heap memory

Performance Tuning is not a simple task. There is no omnipotent solution at all, but you can use some basic principles to implement it. In general, performance tuning is the role of DBA. however, DBA does not have time to carefully check every change made to the stored procedure. so learning some basic

, default is 2 Reviews: These two parameters control the merging and splitting of the PG directory, and when the number of files in the directory is less than filestore_merge_threshold that, the object files of the directory are merged into the parent directory, and if the number of files is greater than the directory filestore_merge_threshold*16*filestore_split_multiple , the directory is split into two subdirectories. Set a reasonable

Basically, the main considerations for Hibernate performance tuning are as follows:? database Design Tuning? HQL optimization? Proper use of APIs (e.g., different collections and query APIs based on different business types)? Main configuration parameters (log, query cache, fetch_size, batch_size, etc.)Map file optimiz

indicates how many new connection requests are allowed to wait in the queue when all threads are used to process requests. When the queue is full, any new request will be rejected. The default value is 100.The configuration example is as follows: Maxthreads is the maximum number of threads started by Tomcat. The default value is 200. acceptcount is the number of requests queued when the number of threads started by Tomcat reaches the maximum. The default value is 100, the two values work toget

ObjectiveAfter getting started with the JVM garbage collection mechanism, you can then learn the performance tuning. There are two main parts of the content: The use of JDK tools. Tuning strategy. Weapon Spectrum JPSList the running virtual machine processes, using the following:JPS [-option] [HostID] Options function

1 read the Apache configuration optimization recommendations below, then adjust the relevant parameters to observe the status of the server.2 Apache Configuration Tuning Recommendations:3Enter/usr/local/apache2/conf/under the extra directory4 Apache optimization,5 after the above operation, Apache has been able to run properly. However, for sites with a slightly larger number of accesses, the Apache default

Liferay The default is not to turn on tuning parameters, so run slower, we can open some parameters to achieve better performance: Today I did the following configuration: (1) The following parameters are configured in the $liferay_home/portal-ext.properties: Last.modifie

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

PID is not appropriate. In this mode, the live sub-argument is not valid.- J Pass parameters to the JVM that Jmap started.Examples are as follows:After obtaining the heap snapshot file, we can use a variety of tools to analyze the file, such as JHAT,VISUALVM.5.jhat: You can parse a Java application's heap snapshot file in the following syntax format:Jhat after the analysis is complete, use the HTTP server to show the results of the analysis, and acce

Web server itself to obtain the best performance, each Apache connection uses a process, so it will not be affected, but a single process Web server, such as Zeus is a file descriptor for each connection, therefore, it is easy to be affected by the default limit.The file opening limit is a limit that can be adjusted using the ulimit command. The ulimit-aS command displays the current limit, and the ulimit-aH command displays the hard limit (before Ke

-party applications running on Linux, there are many performance tuning techniques that can help you improve the performance of your Linux servers and lower your operating costs.14. Correct configuration of MySQLTo allocate more memory to MySQL, you can set the MySQL cache size, and if the MySQL server instance uses more memory, reduce the cache size and increase