- 1. Caching and tuning funfor high scalability Wim Godden Cu.be
Solutions
2. Who am I ?Wim Godden (@wimgtr)Owner of Cu.be Solutions
(http://cu.be)Open Source developer since 1997Developer of
OpenXZend Certified EngineerZend Framework Certified EngineerMySQL
Certified Developer 3. Who are you ?Developers ?System/network
engineers ?Managers ?Caching experience ? 4. Goals of this
tutorialEverything about caching and tuningA few techniques How-to
How-NOT-to Increase reliability, performance and scalability5
visitors/day 5 million visitors/day(Dont expect miracle cure !) 5.
LAMP 6. Architecture 7. Test page3 DB-queries select firstname,
lastname, email from user where user_id = 5; select title,
createddate, body from article order by createddate desc limit 5;
select title, createddate, body from article order by score desc
limit 5;Page just outputs result 8. Our base benchmarkApachebench =
useful enoughResult ?Single webserverProxyStatic PHP Static
PHPApache + PHP3900 17.56700 17.5Limit : Limit :CPU, network
databaseor disk 9. Caching 10. What is caching ?CACHE 11. What is
caching ? x = 5, y = 2 Same resultn = 50 CACHE select * from
articlejoin user Doesnt changeon article.user_id = user.idall the
time order by created desc limit 10 12. Theory of cachingDBle t ab
fro m ul t res ata ned e ct d retursel ta = $da if ($data == false)
Page GET /pageset( key, $$dafals data)ta = eget( key)Cache 13.
Theory of cachingDBHITCache 14. Caching techniques#1 : Store entire
pages #2 : Store part of a page (block) #3 : Store data retrieval
(SQL ?) #4 : Store complex processing result #? : Your call !When
you have data, think :Creating time ?Modification frequency
?Retrieval frequency ? 15. How to find cacheable dataNew projects :
start from cache everythingExisting projects : Look at MySQL slow
query log Make a complete query log (dont forget to turn it off !)
Check page loading times 16. Caching storage - DiskData with few
updates : goodCaching SQL queries : preferably notDONT use NFS or
other network file systems especially for sessions locking issues !
high latency 17. Caching storage - Disk / ramdiskLocal5 Webservers
5 local cachesHow will you keep them synchronized ? Dont say NFS or
rsync ! 18. Caching storage - Memcache(d)Facebook, Twitter,
YouTube, need we say more ?Distributed memory caching
systemMultiple machines 1 big memory-based hash-tableKey-value
storage systemKeys - max. 250bytesValues - max. 1Mbyte 19. Caching
storage - Memcache(d)Facebook, Twitter, YouTube, need we say more
?Distributed memory caching systemKey-value storage system Keys -
max. 250bytes Values - max. 1MbyteExtremely fast... non-blocking,
UDP (!) 20. Memcache - where to install 21. Memcache - where to
install 22. Memcache - installation & running itInstallation
Distribution package PECL Windows : binariesRunning No config-files
memcached -d -m -l -p ex. : memcached -d -m 2048 -l 172.16.1.91 -p
11211 23. Caching storage - Memcache - some notesNot fault-tolerant
Its a cache ! Lose session data Lose shopping cart data ... 24.
Caching storage - Memcache - some notesNot fault-tolerant Its a
cache ! Lose session data Lose shopping cart data Firewall your
Memcache port ! 25. Memcache in code
