Quotations tagged scaling
When I worked at Amazon.com we had a deeply-ingrained hatred for all of the SQL databases in our systems. Now, we knew perfectly well how to scale them through partitioning and other means. But making them highly available was another matter. Replication and failover give you basic reliability, but it’s very limited and inflexible compared to a real distributed datastore with master-master replication, partition tolerance, consensus and/or eventual consistency, or other availability-oriented features.
Scoble writes something—6,800 writes are kicked off, 1 for each follower. Michael Arrington replies—another 6,600 writes. Jason Calacanis jumps in—another 6,500 writes. Beyond the 19,900 writes, there’s a lot of additional overhead too. You have to hit a DB to figure out who the 19,900 followers are. [...] And here’s the kicker: that giant processing and delivery effort—possibly a combined 100K disk IOs—was caused by 3 users, each just sending one, tiny, 140 char message. How innocent it all seemed.
... Facebook has roughly 200 dedicated memcached servers in its production environment, plus a small number of others for development and so on. A few of those 200 are hot spares. They are all 16GB 4-core AMD64 boxes, just because that’s where the price/performance sweet spot is for us right now.
In the big picture, Twitter did exactly the right thing. They had a good idea and they buckled down and focused on delivering something as cool as possible as fast as possible, and it’s really hard, in early 2007, to beat Rails for that. When all of a sudden there were a few tens of thousands of people using it, then they went to work on the scaling.
The promise [of J2EE] was that of infinite scalability based on tooling, which assumes that designing scalable systems is a general case problem. I now firmly believe that this is flawed reasoning. Frameworks don’t solve scalability problems, design solves scalability problems.
None of these scaling approaches are as fun and easy as developing for Rails. All the convenience methods and syntactical sugar that makes Rails such a pleasure for coders ends up being absolutely punishing, performance-wise.