The document discusses tools and techniques for building low-cost, scalable web applications. It recommends using a *nix operating system for stability and low cost. It emphasizes performance and scaling through techniques like caching, clustering, database replication, and scaling out to additional servers. It also discusses reducing network latency through content delivery networks and storing and replicating data across servers using services like Amazon S3.

1. Building Low Cost Scalable Web Applications - Tools & Techniques Ramesh Rajamani Compassites Software Solutions, Bangalore Barcamp, Hyderabad 16 th February 2008

2. Needs Scale seamlessly High Performance Unlimited storage expansion Reduce Network Latency Direct the user to nearest server Scale out, no Scale in Sweet spot: Low Cost, High Performance, Scaleable

3. First & Foremost Operating System makes a difference Go for a *nix based operating system for your production environment Why? Stability Low Cost of Ownership Better security and resource management Better control Support for languages, tools, frameworks etc. Exception - .Net

4. Points of Focus Performance Scaling Network Storage & Replication

5. Performance Identify areas of bottlenecks Example - Huge database reads Cache repeated reads Memory Clustering Use MemCached High-performance, distributed memory object caching system Replicated Hash Table Powerful high performance state replication Java/J2EE - Terracota Virtual Heap POJO clustering

6. Performance (2) Example 2 - Lot of uploads and downloads You can build a low cost grid computing A simple set of scripts and webservices can do the magic Reference IBM article Amazon Web Services - EC2 and S3 if you want to save some time Database Clustering C-JDBC – Database clustering and replication solution for Java/J2EE Apps

7. Scaling Look for easy and quick scaling Customers will be happy if you suggest a low cost solution Scale Out Vs Scale In Build a farm of low cost servers Amazon Web Services EC2 Elastic Computing Quickly add/remove instances via web service calls Pay for processor/networking per hour

8. Reduce Latency Global user access? Route the user to the nearest data center Solution - Content Delivery Network (CDN) Globule - CDN module for Apache Low cost solution providers are available Work step by step Key challenge - Replication of information across servers Domain Name mapping across servers Dynamic Domain Mapping EasyDNS EZ- IPUpdate

9. Storage and Replication Amazon Simple Storage Service (S3) Unlimited storage Transparent Grid computing Not just for file storage but for database as well Replication Database Daffodil Replicator SymmetricDS Document Management Thrudb – Built on top of Facebook’s Thrift framework Scaleable Messaging Spread - Reliable and scalable messaging and group communication

10. Logical Architecture

11. Roadblocks Lot of work R&D Proof of Concepts Integration Issues Multiple point of failures Day 1 won't be a perfect world Learn and improvise Mitigation Be visionary Get the business vision Start working early on Risk Management Bottlenecks Point of failures Sizing and Capacity Planning

12. Q&A

13. About Blog - TechMasala - http://www.techmasala.com Co-founder and Architect, Compassites Software Solutions, Bangalore - http://www.compassites.net Co-Author - Java Servlet Programming Bible - John Wiley - 2002