I have a photo-hosting website, and I want to keep track of views to the photos. Due to the large volume of traffic I get, incrementing a column in MySQL on every hit incurs too much overhead.
I currently have a system implemented using Memcache, but it's pretty much just a hack.
Every time a photo is viewed, I increment its photo-hits_uuid key in Memcache. In addition, I add a row containing the uuid to an invalidation array also stored in Memcache. Every so often I fetch the invalidation array, and then cycle through the rows in it, pushing the photo hits to MySQL and decrementing their Memcache keys.
This approach works and is significantly faster than directly using MySQL, but is there a better way?
I did some research and it looks like Redis might be my solution. It seems like it's essentially Memcache with more functionality - the most valuable to me is listing, which pretty much solves my problem.