Database Sharding Blog

Poornima, a database engineer at mint.com with experience in performance and scalability monitoring and testing, wrote a very interesting blog yesterday about addressing Web application scalability before it is too late. Poornima's starts by making a point that is often overlooked by engineers - the starting point for scalability is 'a business perspective' - because scalability failures are business failures and because scalability requirements are business requirements.

Poornima provides a simple explanation of why Database Sharding works so well for database-driven Web applications:

I’m sure we’ve all learned from our intro computer architecture class that CPU bound processes are the fastest and can be parallelized, whereas I/O processes are the bottleneck. In the case of a website, accessing the DB is the slowest I/O process. However, you can speed up access to data by sharding the database. Sharding breaks up a large database into smaller pieces that contains redundant information or a parent db can map data to separate dbs.

Poornima concludes that scalability problems are often good - because they indicate a growing business - but you should plan for scalability from the start.

Labels: Database Sharding, Scalability Architecture