webroot performance issues

data (-a), log it to the file/var/log/sar/sar.log, collect it every 600 seconds (or 5 minutes), and continue to run in the background. If we want to show this data next, we can add the-f parameter with the SAR command, for example:$ sar-a-f/var/log/sar/sar.logThis is a very basic introduction to the SAR command. With the SAR command, many useful data can be obtained, which makes it more convenient and effective to view the host's performance. I sugge

Translation: Code Performance Adjustment Performance Tuning of code the http://www.newlc.com/performance-tuning-code application runs properly and can execute all the tasks required by the user or the customer, and does not mean that the program is perfect in any way. Using performance analysis tools, such as profiler,

Go from: http://blog.devdlh.com/blog/2013/03/18/performance-problerm-caused-by-shadowpath/drawing Shadow raised IOS drawing performance Issues SummaryMAR 18TH, 2013 | COMMENTSIn IOS development, you can easily add a shadow effect to UIView by setting the Shadowcolor, Shadowopacity, Shadowoffset, and Shadowradius properties of the layer. However, the previous time

cache it, so that the next time the user loads, it is directly out of the cache, the efficiency is fast.For a Web site, CSS, JavaScript, logos, icons, these static resources file updates are relatively low frequency, and these files are almost every time the HTTP request is required, if you cache these files in the browser, can improve performance very well. By setting the properties of Cache-control and expires in the HTTP header, you can set the br

Java Design Polling thread performance issues with while loopThe polling thread is widely used in the development process, where I simulate a scenario that has a queue and polling thread, the main thread queues messages into the queue, and the polling thread loops through the queue to read the message and print the message content. A bit like handler in Android sends messages. First define a message class.p

About performance issues with the for each statement in Java7Today I did a full-array algorithm on leetcode , and I had the right results in my eclipse, but when I submitted it to Leetcode, I reported the result of "time Limit exceeded" .The permutation problem on LeetcodeI began to wonder, in the Leetcode search for a lot of similar problems encountered, but did not find the same as the problems they encou

; Method 2--8.8877 100000 times: Method 1--15.3749; Method 2--65.5758 Or is method 1 less time-consuming? If you don't accept it, I can't help it. I believe it. So why is this result? Cause description View the source code of the sum method of LINQ. The Code is as follows: public static int Sum(this IEnumerable Obviously, every time you call the Evaluate Method of LINQ, the set is traversed. Therefore, method 2 traverses the set five times, and method 1 only needs to traverse the set once,

Review compatibility issues from the JavaScript array, and performance optimization (from yuber blog), javascript yuberReason JavaScript array deduplication is often used in front-end pen questions, such: There are arrays var arr = ['A', 'B', 'C', '1', 0, 'C', 1, '', 1, 0], use JavaScript to implement the unqiue function so that unique (arr) Returns ['A', 'B', 'C', '1', 0, 1, ''] As a pen exam, there are

these tables in steps.Other circumstances. You should control the use of temporal tables and table variables.Note the collation.About temporal table generation use SELECT into and create TABLE + INSERT into options.6. Avoid using cursorsFor some line-by-row processing, consider putting the clientConsider using an associated subquery instead of a cursorThe following issues must be noted when using cursors:Use an efficient cursor type (such as forward-

This article was reproduced from: http://blog.csdn.net/yuanyuanispeak/article/details/527561671 PrefaceThe database large concurrency operation takes into account the deadlock and lock performance issues. See online most vague (especially update lock), so here is a concise explanation, for the following description of the convenient, here with T1 for a database execution request, T2 represents another reque

Locating performance issues, especially when CPU usage is high, often requires finding threads with higher CPU consumption and then looking at their stacks to get into code positioning issues.In this scenario, Jstack+top is a very classic way.jstack+top: 1, top-h view CPU-intensive threads, log a decimal thread id2, Jstack dump thread information into a file, and find the thread's stack based on the thread

production environment can not use full async, because in addition to some times, our server down may lose some important log information, there may be the following blog described the problem78939031Of course, in addition to this problem, there is a hole that others have stepped on here to sharehttps://juejin.im/post/5b7d5b34518825430810be8eFinally, there are some usage methods and configuration information for LOG4J2A detailed explanation of the configuration of the Log4j2Https://www.cnblogs.

A few days ago an old system encountered a performance problem, an upload, there are more than 1000 lines of verification. A piece of data, upload quickly, when uploading two hundred or three hundred, the moment is slow change, it takes 1 hours to feedback results.After troubleshooting, the original is Sqlreader.read () read data after completion, have not done sqlreader.close () shutdown sqlreader, resulting in a large number of database connections

attributes attribute of the element, access the Special collection: Document.fo Rm/document.images. The list of elements that access the DOCUMENT is expensive and should minimize access to the element list.// var imageList = document.getElementsByTagName ("img"); // imagelist:nodelist // Good Example for (var i = 0, len = imagelist.length; i // use Len to save imagelist.length instead of accessing imagelist.length every time. 　　　　　　　　　　　　　　　　var image = Imagelist[i]; // use image to keep t

performance issues with spring's jdbctemplate batch update These two days accidentally found a jdbctemplate batch update performance problem, the problem is such a one-time bulk Delete and insert 3,000 records, incredibly used 400s I was also frightened. I also looked at the code is really using the JdbcTemplate batchupdate method, the usage is not wrong, the no

completion.Solution:Locating the problem, why did you build the index but why not go to index? The key point here actually I didn't have to explain that policy_code this thing is VARCHAR2 classType, and the incoming parameter is number, then the problem comes, the Oracle will do implicit conversion, the rule is to turn left to the right or the right to the left or the right side of the leftTurn Balabala together, the result is that there is no problem with the execution, but the index is not go

Background:New servers that require increased performance monitoring to find that performance metrics cannot be read through PowerShellWorkaround: Open the Registry Editor by going to the Start Menu and selecting Run ..., then type "regedit", and click the OK button. Navigate to the HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\SecurePipeServers\winreg registry key. Right click on t

execution plan you can see that the performance improvement is still very large. This is the data of the test environment, if the data volume is large, the advantage is more obvious.So for this problem, the cause is that there is a job data processing frequency is relatively high, in the test environment is difficult to locate where there is a problem, and the speed can also be accepted, but in the production environment is always slower, in fact, th

Implements a simple task system (task Scheduler) for multi-threaded task execution.Due to programming negligence, a thread multithreading created than the actual hardware line is used to perform the task.Part of the task execution, in the profiling tool, has been a time-consuming part.After discovering this problem, the whole execution time is almost half the same.Specific theoretical explanations can be seen in this article:http://www.codeguru.com/cpp/sample_chapter/article.php/c13533/ Why-too-

SQL Server uses cursors to deal with the extremely competitive performance of Tempdb-DBA issues-required by programmers, tempdb-dba Competition in SQL Server tempdb allocation is a common issue for DBAs. Almost all DBAs now know how to create several more files to solve/alleviate the problem. however, deep competition is inevitable. this section analyzes the features of the cursor in tempdb so that it can r