performance profiling

Performance Optimization GPROF, a program performance analysis tool in Linux GPROF is installed in the/usr/bin directory of Linux. It analyzes your program and determines which part of the program is the most time-consuming. GPROF will tell you the number of calls to each function in the program and the percentage of time each function is executed. This information is useful if you want to improve the

End | 0.000057 | 0.000000 | 0.000000 | | Closing Tables | 0.000061| 0.000000 | 0.000000 | | Freeing items | 0.000080 | 0.000000 | 0.000000 | | Logging Slow Query | 0.000056 | 0.000000 | 0.000000 | | Logging Slow Query | 0.000098 | 0.000000 | 0.000000 | | Cleaning Up | 0.000059 | 0.000000 | 0.000000 | +------------------------------+-----------+----------+------------+ rows in Set (0.00 sec) Ps:Show profiles all for QUERY 2 can also be obtained by using the SELECT * from information_schema.p

" to view their size in real time. 1. ccmalloc-simple memory leakage and malloc debugging libraries for C and C ++ programs in Linux and Solaris. 2. dmalloc-Debug malloc library. 3. electric fence-malloc () debugging library written by Bruce perens in the Linux distribution. 4. leaky-programs for detecting memory leaks in Linux. 5. leaktracer-Linux, Solaris, and HP-UX tracking and analysis of memory leaks in C ++ programs. 6. memwatch-written by Johan Lindh, is an open-source C language memory e

interface function while encapsulating some of the application logic. Server-side database servers primarily provide data storage capabilities, and also provide partial application logic through triggers and stored procedures. C/S/S structure is the client/application server/Database server three-tier structure, the middle of the addition of application server, usually implement the application logic, is the connection between the client and the database server bridge. It responds to requests f

Some time ago in the performance analysis of the company's projects, from a simple analysis of log (GC log, postgrep log, Hibernate statitistic), through the AOP to collect software running data, to pet testing, feel time spent a lot, performance also has a certain increase, But it always feels like working in primitive times, unable to be simple and smooth, and to achieve the desired result with great clar

when it is federated.8, Sub_part If the column is only partially indexed, the number of characters that are indexed. Null if the entire column is indexed.9. Packed indicates how keywords are compressed. Null if it is not compressed.10, NULL if the column contains null, it contains Yes. If not, the column contains No.11, Index_type used Index method (btree consecutive reading data, hash suitable for random reading data, rtree suitable for a data to find nearby data).12. Commentary on CommentShow

Some time ago in the performance analysis of the company's projects, from a simple analysis of log (GC log, postgrep log, Hibernate statitistic), through the AOP to collect software running data, to pet testing, feel time spent a lot, performance also has a certain increase, But it always feels like working in primitive times, unable to be simple and smooth, and to achieve the desired result with great clar

This article mainly introduces the use of the show Profile command in MySQL to analyze the performance of the collation, show profiles is a common command of database performance optimization, the need for friends can refer to the followingShow profile was donated by Jeremy Cole to the MySQL community version. The default is off, but session level can turn on this feature. Opening it allows MySQL to collect

run on the production firehose, and the performance wasn ' t Satis Factory. Profiling showed a lot of time spent in the atomic ASM wrapperruntime·xchg(shown below) andruntime·futex. These atomics is used in various places by the runtime:the memory allocator, GC, Scheduler, locks, semaphores, et al. In we profile, they were mostly descendent Fromruntime chansend andselectgo , which is part of Go ' Schann

https://www.devexpress.com/Support/Center/Question/Details/T148978The best of the determine the precise cause of a performance problem are to profiles your application using a specialized performance Profiler tool, e.g, aqtime, ANTS Performance Profiler (if you were developing a Web app, then Additiona Lly Profile The client side operation using the deve

obtain more performance data about the task, click Start method profiling )". Analyzer only collects a small amount of data (not seen for more than 2 or 3 seconds), so click the icon again in a few minutes to stop collection. Activating the method analyzer from ddms enables the tool to automatically use internal storage to store analysis results. After capturing is complete, they are sent back to the host

This article describes how to use the showprofile command in MySQL to analyze performance. showprofiles is a common command for database performance optimization, for more information, see how to donate the show profile to the MySQL community by Jeremy Cole. This feature is disabled by default, but can be enabled at the session level. Enabling It allows MySQL to collect resources used during statement execu

application encountered. (This also gives away the information on performance bottlenecks-I. e. Where your application has Ds the most of its time .) So what I did to demonstrate this was write a very simple application which displays prime numbers in a given range. it's written in a very inefficient way so that it takes quite some time to execute. to profile what's going on inside, I went to the AdministrativeCommand Prompt again and typed: xperf -o

Recently, I 've been struggling with how to analyze and tune performance, starting with hardware orCodeOr database. From the Operating System (CPUScheduling, memory management, process scheduling, DisksI/O), Network, protocol (HTTP,TCP/IP), Or from the applicationProgramCode, database optimization, and middleware configuration. Multiple MiddlewareWebMiddleware (Apache,IIS), Application Middleware (Tomcat,WebLogic,WebSphere) And so on. Even though the

Build high performanceASP. NETSite Chapter 5-Performance Tuning Overview (previous) During this time, the seriesArticleI reorganized it. The previous introduction to performance optimization was not very clear. It can be said that starting from this article, it is the beginning of a complete series. Links to articles: Build high performanceASP. NETSite Opening Build high performanceASP. NETO

ability to copy different size files in different buffer sizes, pipeline throughput, Process generation speed, system call overhead, and so on to test Linux -related performance. XbenchThe main test Xwindow graphical interface performance. IOzone File System Evaluation tool for read , write re-read Re-write read Backwards read strided,fread,fwrite,Random Read,pread , mmap , Aio-read , Aio_write

percent. In order to ensure that the data analysis in the unified use of the scene is really implemented there are the following points to note: When starting an application profiling, be sure to use the real machine, the emulator running on the MAC, while the CPU on the MAC is often faster than the iOS device. On the contrary, the GPU on the Mac is completely different from the iOS device, and the simulator has to simulate the device's GPU at the so

filtered, so some where statements do not appear in the extra column with a using where such a descriptionThe new feature after using index condition:mysql5.6 will conditionally filter the index, filter the index to find all rows of data that match the index criteria, and then filter the data rows with other conditions in the WHERE clauseUsing temporary:using Temporary: This means that MySQL uses a temporary table when the query results are sortedUsing Filesort: Cannot use index when sorting, n

This article is originally from abroad this article: PHP performance Evolution 2016, thanks to the high-availability architecture of the public number translated into the Chinese version, here is reproduced in the highly available architecture translated articles from PHP 5 to PHP 7 performance full evaluation (including the unpublished JIT version of PHP 8 contrast), A slightly adjusted format.Introduction

among the top four in 22 of the 24 tests. Although JVM uses performance profiling to optimize only common code paths, this optimization is very effective. In many cases, the Java code compiled by JIT is as fast as that compiled by C ++, and more such cases exist. However, some people still think that the Java platform is slow, which may be due to the historical bias of those who have experienced earlier ve