Site Optimization and the Law of Diminishing Returns

If you have reading my blog, site optimization has always been apart of my development.  Techniques like rewriting slow sql queries and in memory caching will boost the performance of your site and reduce the need of purchasing more hardware. 

Currently myVidster's growth is at 16% (Source: Google Analytics).  While this is great, I have to activity monitor the site to ensure that performance stays optimal.  Most pages like the homepage, video bookmark and user profile will load within a second even during peak traffic.  Performance starts to take a hit when viewing a collection homepage and user subscription page when the video bookmark count are in the 1k+ range.  In this case performance is reduce to 2-4 seconds.

In response I have spent the last few weeks combing though my code and doing some house keeping cleaning up my code and updating sql queries.  In the end I was only able to increase performance by 500-1000ms.  On the bright side I did reduce the memory consumption of my PHP processes :).

Now we enter the Law of Diminishing Returns.  Do I spend more time trying to optimize my code or do I upgrade or add new hardware?  I know I can only do so much optimization before I get to the point that the benefits no longer justify the time I am spending (time is money).  You also have side affects where an update intended for optimization breaks or limits site's functionality.

With that said, I will most likely add a new server to handle myVidster's growth.  I being a geek always enjoy adding a new server to the family.  Well that is all for now, take care and keep collecting!