performance tuning books

), or (or), and not (non). Not can be used to negate any logical operation symbol. The following is an example of a NOT clause: ... where not (status = ' VALID ') If you want to use not, you should precede the phrase with parentheses and precede the phrase with the NOT operator. The NOT operator is included in another logical operator, which is the not equal to ( . : Where status For this query, it can be rewritten to not use not: SELECT * FROM employee where salary Although the results of thes

This article is a systematic summary of the consumption analysis in performance tuning.For additional space on the Performance tuning series, see.Performance Tuning: CPU consumption analysisPerformance tuning: IO consumption analysisPerformance

Tags: phone media font insert mode send com debug = =ObjectiveAn engineer at Microsoft once had a very figurative metaphor for performance tuning: Peeling onions. I also very much agree, let us to a layer of a layer of the outside its mysterious veil. Six major factorsThe following are the most common diagrams we use to analyze database performance issues for ou

This article transferred from: http://www.cnblogs.com/chen77716/archive/2010/06/26/2130807.htmlRecent memory leaks due to the project, so large-scale JVM performance tuning, now the experience to do a record.First, JVM memory model and garbage collection algorithm1. According to the Java Virtual Machine specification, the JVM divides the memory into: New (Young Generation) Tenured (old generati

different tables or libraries)Five, server side and client interaction optimization:Client tries to reduce requestsLogical processing of the service side as long as possibleServer-side and client-driven push-pull combination (can take advantage of some synchronization mechanisms)Optimization of communication protocols. (Reduce the size of the message)Power usage optimization (try not to use background execution)Vi. Non-technical performance optimizat

IIS Performance Tuning 1. Adjust the IIS cache The range of HKEY_LOCAL_MACHINE Systemcurrentcontrolsetservicesinetinfoparametersmemorycachesize Memorycachesize is from 0 4GB, The default value is 3072000 (3MB). In general, this value should be set to 10% of the server memory. IIS improves system performance by caching system handles, directory listings, and oth

Detailed configuration: port= "protocol=" "http/1.1"connectiontimeout= "20000"redirectport= "8443"/> 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, th

should precede the phrase with parentheses and precede the phrase with the NOT operator. The NOT operator is included in another logical operator, which is the not equal to (... where status For this query, it can be rewritten to not use not:SELECT * FROM employee where salaryAlthough the results of these two queries are the same, the second query scenario is faster than the first query scenario. The second query allows Oracle to use indexes on salary columns, while the first query cannot use i

for download. 　　11. Avoid redirection The redirection of a Web page can incur additional overhead, so you want to avoid a redirection of the page to a jump operation. 　　12. Delete duplicate scripts A page containing the same JavaScript file two times can affect the performance of the load, so you need to delete the duplicate script files. 　　13. Configure ETag This is a puzzling question. In theory, the etag deletion of the server will improve t

Label:20 Experience tuning MySQL performance optimizationPublished: February 15, 2012 published by: OurmysqlSource: Web Base is read: 3,354 kills 0 comments This article will introduce you to 20 MySQL performance optimization experience, these little experiences will help you better use MySQL for web development. Today, database operations are increasingly bec

This article mainly describes the problem of DB2 Performance Tuning. We mainly answer the problems in DB2 performance tuning in a one-Question-and-one manner, the following is a description of the DB2 Performance Tuning problem. I

rate is too high is not continue to decline). The attenuation learning rate can be adopted, and the learning rate is gradually attenuated with the training. Take 0.5. For example, when Val loss meet No-improvement rules, should have taken early stopping, but can not stop, but let learning rate half continue to run. So repeatedly. Attenuation methods are: attenuation to a fixed minimum learning rate linear attenuation, exponential decay, or 2-10 times as much attenuation per Val loss stagnation.

means a survivor area consumes 1/8 of Eden memory, or 1/10 of the Cenozoic memory) PermSize = 268435456 (256.0MB) # #perm区大小 MaxPermSize = 268435456 (256.0MB) # #最大可分配perm区大小Heap Usage: # #堆使用情况New Generation (eden + 1 Survivor space): # #新生代 (Eden District + survior) capacity = 322109440 (307.1875MB) # #新生代容量307M used = 226237024 (215.75643920898438MB) # #已经使用大小215M free = 95872416 (91.43106079101562MB) # #剩余容量91M 70.23607380150051% used # #使用比例70%eden

Document directory Configuration Optimization Others Hbase client Optimization Link: http://kenwublog.com/hbase-performance-tuning 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 configu

poorly run applications outweigh the investment in human, program, and technology using reliable load testing methods. Therefore, I would like to provide the following list of load tests for your application, which will be a magic bullet to prevent your SQL Server performance tuning problem. Checklist: Load test--sql server performance

indexes are fully utilized during execution. normally, if the index is fully utilized, the name of the execution step will be index seek. note: When analyzing Io, You need to execute the set statistics Io on statement to open the IO analysis.4. Based on the analysis results, add the corresponding indexes and reduce the I/O later.5. for stored procedures, the event viewer should be used to further filter their information. If spid is used (which can be obtained through select @ spid), then the m

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

change the concurrency count to 200. found that about 50% of the return to 502. Then I will keystone-api instead of Keystone own service Openstack-keystone. Again with 200 concurrent pressure test: The discovery processing is normal, did not return 502. Ab-r-N 100000-c 200-h "user-agent:python-keystoneclient"-H "accept:application/json"-H "x-auth-token:65e194" htt p://keystonehost:35357/v2.0/ Probably know that the problem should be on nginx and UWSGI, limiti

MySQL performance tuning and Architecture Design-Chapter 1 Data splitting of scalability design and mysql Optimization Chapter 1 Data splitting for scalable design Preface The expansion implemented through the MySQL Replication function is always limited by the size of the database. Once the database is too large, especially when writing too frequently, it is difficult to support it by a host, we are still

) name:@"IdleNotification" object:nil]; NSNotification *notification = [NSNotification notificationWithName:@"IdleNotification" object:nil]; [[NSNotificationQueue defaultQueue] enqueueNotification:notification 　　postingStyle:NSPostWhenIdle];} Five, memory optimization Use Autorelease pool to reduce memory spikes Six, Code details optimization 1, not in the viewwillapear time-consuming operation 2. If the key code is more efficient with C/C + + Seven, picture optim