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Presented by:
         Bill Takacs – Director, Product Management


September 2009
Agenda

     •!Rise of the dynamic web!


     •!The web architecture!


     •!The evolution of a dynamic site and Memcached!


     •!Gear6 solution!




2 : Copyright 2009 Gear6 Inc.
The Web: What’s Changed?

     •!Population!

     •!Tra"c!

     •!Content and applications!




3 : Copyright 2009 Gear6 Inc.
Web Growth: Population

          Forrester: 2.2 billion people online globally by 2013




4 : Copyright 2009 Gear6 Inc.
Web Growth: Traffic

        Cisco: “Annual global IP traffic
     will exceed two-thirds of a zettabyte
         (667 exabytes) in four years”
                   [by 2013]
                     Source: Cisco Visual Networking Index,
                                  9 June 2009




5 : Copyright 2009 Gear6 Inc.
Web Growth: Application & Content



                                  Entertainment
                                              !
                                Social Networking!
                                      Media
                                          !
                                 Communication
                                             !
                           Community-generated content
                                                     !




6 : Copyright 2009 Gear6 Inc.
But growth can be
Growth can be painful
                painful
       (VERY)
Web Architecture

    !! Most sites (over 65%) based on LAMP or JAVA
    !! Industry standard servers replaced proprietary SMP
    !! Shift to Dynamic Content puts strain on origin sites

                                                           Web Stack                                                         Net
                                                                                                                          Interface
   Storage                                                                                                                                       Clients
                                                            PHP, Java, Rails, C,
                                               Database!




                                                                                                                                      Internet
                                                                                              Apache, Nginx,
                                                                                   Servers!



                                                                                                               Servers#
                                                              Perl, Python!
                                PostgreSQL !




                                                                                                Lighttpd!
                                  MySQL,




                                                                                                                Web
                                                                                     App

                                                                                                                           Proxy
                                                                                                                                       CDN!

                                                                                                                           Load
                                                                                                                          Balancer




8 : Copyright 2009 Gear6 Inc.
What to do?




9 : Copyright 2009 Gear6 Inc.
New Caching Architecture
     for Scaling Out

                                                            Web Stack                                                         Net
                                                                                                                           Interface
    Storage                                                                                                                                       Clients



                                                             PHP, Java, Rails, C,
                                                Database!
                                                                                                                                       Internet




                                                                                               Apache, Nginx,
                                                                                    Servers!



                                                                                                                Servers#
                                                               Perl, Python!
                                 PostgreSQL !




                                                                                                 Lighttpd!
                                   MySQL,




                                                                                                                 Web
                                                                                      App
                                                                                                                            Proxy
                                                                                                                                        CDN!

                                                                                                                            Load
                                                                                                                           Balancer

                                                                      Cache Servers
                                                                                     memcached




10 : Copyright 2009 Gear6 Inc.
Memcached: Pillar of Web 2.0 Architecture




                                 “Everything runs#
                                   from memory#
                                    in Web 2.0”
                                              !
                                  Evan Weaver, Twitter, March 2009!



11 : Copyright 2009 Gear6 Inc.
The Fix: Memcached

            “A high performance, distributed memory object
            caching system, generic in nature, but intended for
             use in speeding up dynamic web applications by
                        alleviating database load”!

     •! Big hash table!

     •! Created by Danga Interactive for LiveJournal!

     •! Significantly reduced database load!

     •! Perfect for web sites with high database load!

     •! In use by Facebook, Twitter, MyYearbook, others!

12 : Copyright 2009 Gear6 Inc.
Evolution of a Dynamic Site #1
     A day in the life of a growing web service


     •! Event: Site has growth in number of users/sessions/page
        views/apps causing excessive read load on DB!
     •! Action: Replicate Database (and/or add more app servers)!


                                                             App Server       App Server        App Server

     App Server           App Server   App Server   App Server       App Server    App Server




                          write!
                                                                 write!                write!
                                                                                  …
                                                            MySQL                     MySQL
                        MySQL




13 : Copyright 2009 Gear6 Inc.
Evolution of a Dynamic Site #2
     A day in the life of a growing web service

    •! Event: Individual caches on the app/db servers are
       overwhelmed from chaotic/non-deterministic content access!
    •! Action: Add memcached server on servers with underutilized
       memory resources… results in even fewer reads to database!



                                                                             memcached            memcached           memcached
           App Server            App Server       App Server                App Server           App Server          App Server
                                                                memcached            memcached           memcached
                                                               App Server         App Server          App Server
App Server         App Server         App Server




             write!                      write!                             write!                        write!
                                   …                                                               …
          MySQL                        MySQL                            MySQL                           MySQL




14 : Copyright 2009 Gear6 Inc.
Evolution of a Dynamic Site #3
     A day in the life of a growing web service

     •! Event: Memcached needs more memory resources than
        what is available on other (shared) servers!
     •! Action: Move memcached servers to dedicated servers!



              memcached            memcached           memcached
             App Server           App Server          App Server             App Server              App Server       App Server
 memcached            memcached           memcached
App Server         App Server          App Server                  App Server       App Server            App Server

                                                                      memcached          memcached         …          memcached




             write!                        write!                               write!                       write!
                                    …                                                                  …
          MySQL                          MySQL                              MySQL                          MySQL




15 : Copyright 2009 Gear6 Inc.
What Memcached is NOT:

                                 A persistent data store!


                                 A database!


                                 Application-specific!


                                 A large object cache!


                                 Fault-tolerant or highly available!

16 : Copyright 2009 Gear6 Inc.
Memcached: Best Practices

     •!Use with MySQL :-)!       •!Careful with
     •!Use on 64-bit               numbers of
       servers!                    connections!
     •!Cache “expensive            »! Peak!
       operations”!                »! Transitions!

     •!Cache bi-                 •!Evictions!
       directionally (R/W)!        »! Segment Memcached
                                      data into separate pools
                                                             !
     •!Design to withstand
                                 •!Optimize sizing:
       failures gracefully!
                                   Instances and pools!
     •!Use consistent
                                 •!Instrumentation!
       hashing!

17 : Copyright 2009 Gear6 Inc.
Memcache Use Cases

          Site Type                 Repeatable Use

          Social networking         Profile caching

          Content aggregation       HTML/page caching

          Ad targeting              Cookie/profile tracking

          Gaming and entertainment Session caching

          Location-based services   DB query scaling

          Relationship              Session caching

          E-commerce                Session and HTML caching

18 : Copyright 2009 Gear6 Inc.
Use Case Example:
     Session Management

                                 •! 4m+ daily visitors!
                                 •! 15k hits/sec!
                                 •! 6k updates/sec!
                                 •! Tens of thousands
                                    concurrent connections!
                                 •! Session tracked and ads
                                    are placed in accordance
                                    to session!




19 : Copyright 2009 Gear6 Inc.
Use Case Example:
     User Targeting Engine

    Recommendations on
      User webpages
                                                               User Targeting Service
                                                                 User Targeting Service
                                                                                                       Memcached
                                                                    User Targeting Service
                                                                Thin/fast memcache
                                                                                                         pool!
                                                                 Client layer memcache
                                                                   Thin/fast (reads)
                                                                    Client layer memcache
                                                                      Thin/fast (reads)
                                                                       Client layer (reads)
                                                                 Update processing
                                 Webserver / php                       (writes)
                                                                    Update processing                                    Bulk/batch
                                   Load Balancer                          (writes)                                       updates
                                                                       Update processing
       Load Balancer
                                      Load Balancer                           (writes)


                                                                                                         Hadoop!
                                                                                      “Lazy” Updates
                                                                                                         Map/Reduce Jobs
                                                                                                          Data processing


                                         User targeting data
                                        From logs and other                                             User profile updates
                                              systems


                                                                   Reports!                               Ad-Hoc Analysis



                                                                                                       Memcache repopulation
                                                                                                       (bulk updates, recovery)




20 : Copyright 2009 Gear6 Inc.
Useful Memcached Tools

                       advanced reporter!
                       Track hot keys and clients in Memcached!

                       wireshark!
                       Dissect and analyze Memcached network tra"c!

                       brutis!
                       Size and test changes to memcache clusters!

                       statsproxy!
                       View bu$ered Memcached stats in your browser!

                       cacti!
                       Graph and analyze Memcached statistics!


21 : Copyright 2009 Gear6 Inc.
Statsproxy + Cacti Templates




                                    To use the cacti
                                    templates for
                                    memcached with
                                    statsproxy, you
                                    either need to
                                    modify the
                                    templates to use
                                    port 8080 or
                                    change the
                                    statsproxy config to
                                    use port 11211




22 : Copyright 2009 Gear6 Inc.
•! First and leading provider#
     of Memcached solutions!

  •! Memcached solution including!

          •! High density!

          •! High Availability!

          •! Advanced memory#
             management!

          •! Enhanced reporting#
             capabilities !

          •! Support for multi-tenancy!

          •! Disruption free#
             software upgrades!

          •! 100% client compatible!


23 : Copyright 2009 Gear6 Inc.
Questions?

         Thank you for attending our webinar
                                           !
   “Memcached and the Rise of the New Dynamic Web”!




                                 and please visit our web site at:
                                                                 !
                                 www.gear6.com!
24 : Copyright 2009 Gear6 Inc.
References
     •!   Danga.com!
     •!   Highscalability.com!
     •!   Dev.gear6.com!
     •!   Groups.google.com/group/memcached!
     •!   Code.google.com/p/memcached!
     •!   Twitter.com/gearsix!
     •!   Cacti.net!
     •!   Wireshark.org!
     •!   http://dev.mysql.com/doc/mysql-ha-scalability/en/ha-memcached-
          using-deployment.html!
     •!   http://dev.mysql.com/doc/mysql-ha-scalability/en/ha-memcached-
          using-hashtypes.html!
     •!   http://jayant7k.blogspot.com/2009/04/memcached-replication.html!
     •!   http://www.lexemetech.com/2007/11/consistent-hashing.html!
     •!   http://www8.org/w8-papers/2a-webserver/caching/paper2.htmlhttp://
          www.last.fm/user/RJ/journal/2007/04/10/rz_libketama_-
          _a_consistent_hashing_algo_for_memcache_clients!
     •!   http://bazaar.launchpad.net/~libmemcached-developers/libmemcached/
          trunk/revision/539!
25 : Copyright 2009 Gear6 Inc.

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Memcached and the Rise of the Dynamic Web

  • 1. Presented by: Bill Takacs – Director, Product Management September 2009
  • 2. Agenda •!Rise of the dynamic web! •!The web architecture! •!The evolution of a dynamic site and Memcached! •!Gear6 solution! 2 : Copyright 2009 Gear6 Inc.
  • 3. The Web: What’s Changed? •!Population! •!Tra"c! •!Content and applications! 3 : Copyright 2009 Gear6 Inc.
  • 4. Web Growth: Population Forrester: 2.2 billion people online globally by 2013 4 : Copyright 2009 Gear6 Inc.
  • 5. Web Growth: Traffic Cisco: “Annual global IP traffic will exceed two-thirds of a zettabyte (667 exabytes) in four years” [by 2013] Source: Cisco Visual Networking Index, 9 June 2009 5 : Copyright 2009 Gear6 Inc.
  • 6. Web Growth: Application & Content Entertainment ! Social Networking! Media ! Communication ! Community-generated content ! 6 : Copyright 2009 Gear6 Inc.
  • 7. But growth can be Growth can be painful painful (VERY)
  • 8. Web Architecture !! Most sites (over 65%) based on LAMP or JAVA !! Industry standard servers replaced proprietary SMP !! Shift to Dynamic Content puts strain on origin sites Web Stack Net Interface Storage Clients PHP, Java, Rails, C, Database! Internet Apache, Nginx, Servers! Servers# Perl, Python! PostgreSQL ! Lighttpd! MySQL, Web App Proxy CDN! Load Balancer 8 : Copyright 2009 Gear6 Inc.
  • 9. What to do? 9 : Copyright 2009 Gear6 Inc.
  • 10. New Caching Architecture for Scaling Out Web Stack Net Interface Storage Clients PHP, Java, Rails, C, Database! Internet Apache, Nginx, Servers! Servers# Perl, Python! PostgreSQL ! Lighttpd! MySQL, Web App Proxy CDN! Load Balancer Cache Servers memcached 10 : Copyright 2009 Gear6 Inc.
  • 11. Memcached: Pillar of Web 2.0 Architecture “Everything runs# from memory# in Web 2.0” ! Evan Weaver, Twitter, March 2009! 11 : Copyright 2009 Gear6 Inc.
  • 12. The Fix: Memcached “A high performance, distributed memory object caching system, generic in nature, but intended for use in speeding up dynamic web applications by alleviating database load”! •! Big hash table! •! Created by Danga Interactive for LiveJournal! •! Significantly reduced database load! •! Perfect for web sites with high database load! •! In use by Facebook, Twitter, MyYearbook, others! 12 : Copyright 2009 Gear6 Inc.
  • 13. Evolution of a Dynamic Site #1 A day in the life of a growing web service •! Event: Site has growth in number of users/sessions/page views/apps causing excessive read load on DB! •! Action: Replicate Database (and/or add more app servers)! App Server App Server App Server App Server App Server App Server App Server App Server App Server write! write! write! … MySQL MySQL MySQL 13 : Copyright 2009 Gear6 Inc.
  • 14. Evolution of a Dynamic Site #2 A day in the life of a growing web service •! Event: Individual caches on the app/db servers are overwhelmed from chaotic/non-deterministic content access! •! Action: Add memcached server on servers with underutilized memory resources… results in even fewer reads to database! memcached memcached memcached App Server App Server App Server App Server App Server App Server memcached memcached memcached App Server App Server App Server App Server App Server App Server write! write! write! write! … … MySQL MySQL MySQL MySQL 14 : Copyright 2009 Gear6 Inc.
  • 15. Evolution of a Dynamic Site #3 A day in the life of a growing web service •! Event: Memcached needs more memory resources than what is available on other (shared) servers! •! Action: Move memcached servers to dedicated servers! memcached memcached memcached App Server App Server App Server App Server App Server App Server memcached memcached memcached App Server App Server App Server App Server App Server App Server memcached memcached … memcached write! write! write! write! … … MySQL MySQL MySQL MySQL 15 : Copyright 2009 Gear6 Inc.
  • 16. What Memcached is NOT: A persistent data store! A database! Application-specific! A large object cache! Fault-tolerant or highly available! 16 : Copyright 2009 Gear6 Inc.
  • 17. Memcached: Best Practices •!Use with MySQL :-)! •!Careful with •!Use on 64-bit numbers of servers! connections! •!Cache “expensive »! Peak! operations”! »! Transitions! •!Cache bi- •!Evictions! directionally (R/W)! »! Segment Memcached data into separate pools ! •!Design to withstand •!Optimize sizing: failures gracefully! Instances and pools! •!Use consistent •!Instrumentation! hashing! 17 : Copyright 2009 Gear6 Inc.
  • 18. Memcache Use Cases Site Type Repeatable Use Social networking Profile caching Content aggregation HTML/page caching Ad targeting Cookie/profile tracking Gaming and entertainment Session caching Location-based services DB query scaling Relationship Session caching E-commerce Session and HTML caching 18 : Copyright 2009 Gear6 Inc.
  • 19. Use Case Example: Session Management •! 4m+ daily visitors! •! 15k hits/sec! •! 6k updates/sec! •! Tens of thousands concurrent connections! •! Session tracked and ads are placed in accordance to session! 19 : Copyright 2009 Gear6 Inc.
  • 20. Use Case Example: User Targeting Engine Recommendations on User webpages User Targeting Service User Targeting Service Memcached User Targeting Service Thin/fast memcache pool! Client layer memcache Thin/fast (reads) Client layer memcache Thin/fast (reads) Client layer (reads) Update processing Webserver / php (writes) Update processing Bulk/batch Load Balancer (writes) updates Update processing Load Balancer Load Balancer (writes) Hadoop! “Lazy” Updates Map/Reduce Jobs Data processing User targeting data From logs and other User profile updates systems Reports! Ad-Hoc Analysis Memcache repopulation (bulk updates, recovery) 20 : Copyright 2009 Gear6 Inc.
  • 21. Useful Memcached Tools advanced reporter! Track hot keys and clients in Memcached! wireshark! Dissect and analyze Memcached network tra"c! brutis! Size and test changes to memcache clusters! statsproxy! View bu$ered Memcached stats in your browser! cacti! Graph and analyze Memcached statistics! 21 : Copyright 2009 Gear6 Inc.
  • 22. Statsproxy + Cacti Templates To use the cacti templates for memcached with statsproxy, you either need to modify the templates to use port 8080 or change the statsproxy config to use port 11211 22 : Copyright 2009 Gear6 Inc.
  • 23. •! First and leading provider# of Memcached solutions! •! Memcached solution including! •! High density! •! High Availability! •! Advanced memory# management! •! Enhanced reporting# capabilities ! •! Support for multi-tenancy! •! Disruption free# software upgrades! •! 100% client compatible! 23 : Copyright 2009 Gear6 Inc.
  • 24. Questions? Thank you for attending our webinar ! “Memcached and the Rise of the New Dynamic Web”! and please visit our web site at: ! www.gear6.com! 24 : Copyright 2009 Gear6 Inc.
  • 25. References •! Danga.com! •! Highscalability.com! •! Dev.gear6.com! •! Groups.google.com/group/memcached! •! Code.google.com/p/memcached! •! Twitter.com/gearsix! •! Cacti.net! •! Wireshark.org! •! http://dev.mysql.com/doc/mysql-ha-scalability/en/ha-memcached- using-deployment.html! •! http://dev.mysql.com/doc/mysql-ha-scalability/en/ha-memcached- using-hashtypes.html! •! http://jayant7k.blogspot.com/2009/04/memcached-replication.html! •! http://www.lexemetech.com/2007/11/consistent-hashing.html! •! http://www8.org/w8-papers/2a-webserver/caching/paper2.htmlhttp:// www.last.fm/user/RJ/journal/2007/04/10/rz_libketama_- _a_consistent_hashing_algo_for_memcache_clients! •! http://bazaar.launchpad.net/~libmemcached-developers/libmemcached/ trunk/revision/539! 25 : Copyright 2009 Gear6 Inc.