Apache Performance Tuning.ppt

1、Apache Performance Tuning,Part 1: Scaling Up,Sander Temme ,2,“Apache is a general webserver, which is designed to be correct first, and fast second. Even so, its performance is quite satisfactory. Most sites have less than 10Mbits of outgoing bandwidth, which Apache can fill using only a low end Pen

2、tium-based webserver.”,http:/httpd.apache.org/docs/1.3/misc/perf-tuning.html says:,3,4,Goals of Performance Tuning,Serve as Many Requests as Possible Graceful Degradation (Dont crash the box),5,Assumptions,Limited Resources Work With What You Have Youre probably running Linux No Compiling or Recompi

3、ling! You can find httpd.conf,6,Monitoring Your Server,7,Purposes of Monitoring,Observation Extrapolation Signals/Alerts Testing,8,Monitoring Apache,9,Monitoring Solaris: SE Toolkit,Lightweight Programmable Alive,http:/ Monitoring Tools,vmstat iostat top free,11,12,Web Server Logs,ErrorLog LogLevel:

4、 debug, info, notice, warn, error, crit Access Log: TransferLog or CustomLog Common Log Format,13,Common Log Format,172.16.2.91 - - 16/Nov/2003:15:23:27 -0800 “GET /sctemme/ HTTP/1.1“ 200 1446 172.16.2.91 - - 16/Nov/2003:15:23:28 -0800 “GET /sctemme/css/doc.css HTTP/1.1“ 200 167 172.16.2.91 - - 16/N

5、ov/2003:15:23:28 -0800 “GET /sctemme/css/menu.css HTTP/1.1“ 200 623 172.16.2.91 - - 16/Nov/2003:15:23:29 -0800 “GET /favicon.ico HTTP/1.1“ 404 283 172.16.2.91 - - 16/Nov/2003:15:23:34 -0800 “GET /sctemme/index.html HTTP/1.1“ 200 1446,14,Configuring for Performance,Configuring Apache Tuning the Opera

6、ting System,15,Apache Configuration,Process/Thread Management DNS Lookups Avoid .htaccess Files Disable unused modules Tune your App Tier,16,DNS Lookups,HostnameLookups Access Control Bad: Deny from Good: Deny from 172.160.234.5,17,.htaccess Files,Per-directory configuration files Accessed for ever

7、y request Best performance: AllowOverride none,GET /dir1/dir2/restricted.html HTTP/1.0,18,MaxClients,Configuration file directive Maximum number of workers Apache 1.3, 2.0 Prefork: processes Apache 2.0 Worker: threads * processes Limit according to resources (memory),19,Server-side Includes,We Love

8、Them! Easy to implement Easy to manage We Hate Them! They break sendfile() They break cacheability,20,SSI on www.apache.org,SSI Enabled,21,Sizing MaxClients,Take total RAM Subtract OS allowance look at free value without Apache, etc. Subtract external program allowance JVM, cgi programs, MySQL? Divi

9、de by httpd process size Read process size from top,22,Top,23,Selecting Your MPM,Apache 2.0 only! Processes and Threads Differences between platforms Thread-safety issues,24,Processes and Threads,Process: Own copy of data structures Shares: program code, shared memory Context switches expensive Thre

10、ad: Runs within process Shares process environment No context switch,25,Platforms and Threading,Context switches expensive on Solaris, AIX Context switches cheaper on Linux Solaris uses M:N threading Linux uses 1 process per thread LinuxThreads implementation is old Replaced by Native Posix Thread L

11、ibrary (NPTL) in 2.6 NTPL already in RH 9, RHAS 3,26,Thread-safety,Third-party modules and libraries mod_perl: experimental threading in Perl 5.6; more mature in Perl 5.8 PHP: uses many third-party libraries FreeBSD: threading not reliable until 5.x Apache 2.2 Worker MPM runs on FreeBSD,27,Tune your

12、 App Tier,Tomcat Edit server.xml, tune minProcessors, maxProcessors Use APR - Persistent connections Tune JVM (Heap, Garbage Collection) MySQL Ships with various scenarios in support-files: my-small,medium,large,huge.conf PHP & prefork: every child makes a connection Tune max_connections variable in

13、 f,28,System Tuning Tips,RAM and swap space ulimit: files and processes Turn off unused services and modules,29,RAM and Swap,Swap is disk-based Extension of RAM Excessive swapping kills performance Tune MaxClients Never have more memory than swap Upgrade RAM - add more swap space,30,ulimit,Per-proce

14、ss resource limits Built-in command of sh, bash Important limits:processes (-u) open files (-n) Set in invoking shell Code in Apache 2.0 startup script ulimit -S -n ulimit -H -n Linux: /etc/security/limits.conf,31,Caching Content,Dynamic Content is Expensive Static Content Relatively Cheap Several A

15、pproaches: Dynamic caching Pre-rendering popular pages (index.rss),32,mod_cache Configuration,CacheRoot /raid1/cacherootCacheEnable disk /# A page modified 100 min. ago will expire in 10 min.CacheLastModifiedFactor .1# Always check again after 6 hoursCacheMaxExpire 21600,33,Make Popular Pages Static

16、RSS Feeds Popular catalog queries (Check your access log),34,Static Page Substitution,Options +IndexesOrder allow,denyAllow from allRewriteEngine onRewriteCond %REQUEST_FILENAME !-fRewriteCond %REQUEST_FILENAME !-dRewriteRule (.*)$ /cgi-bin/blosxom.cgi/$1 L,QSA,35,Tips,Observe Before You Act Act on

17、 Monitoring Results Dont Overload Your System,Q&A,37,Conference Roadmap,TH9: Building a Fast and Rich Web App with PHP 5 TH10: Troubleshooting Apache configurations TH19: mod_perl for Speed Freaks! TH22: Garbage collection tuning for java server processes FR12: Getting everything out of Apache Derby

18、 database FR1: Scaling httpd 2.x to 50,000 Concurrent Downloads FR5: Apache Performance Tuning Part 2: Scaling Out FR24: PHP and MySQL Best Practices 2.0,Current Version,http:/people.apache.org/sctemme/ApconEU2006/FR4/,Thank You,40,Further Reading,Ryan B. Bloom, Apache Server 2.0: The Complete Reference, 2002 McGraw Hill Osborne; ISBN 0-07-222344-8 Ben Laurie and Peter Laurie, Apache: The Definitive Guide (3rd Edition), 2002 OReilly ISBN 0596001916,