Simon Willison’s Weblog

cache-money. A “write-through caching library for ActiveRecord”, maintained by Nick Kallen from Twitter. Queries hit memcached first, and caches are automatically kept up-to-date when objects are created, updated and deleted. Only some queries are supported—joins and comparisons won’t hit the cache, for example.

# 28th June 2009, 3:17 pm / activerecord, cachemoney, caching, memcached, rails, twitter

Twitter, an Evolving Architecture. The most detailed write-up of Twitter’s current architecture I’ve seen, explaining the four layers of cache (all memcached) used by the Twitter API.

# 28th June 2009, 3:09 pm / architecture, caching, memcached, twitter

peeping into memcached. “Peep uses ptrace to freeze a running memcached server, dump the internal key metadata, and return the server to a running state”—you can then load the resulting data in to MySQL using LOAD LOCAL INFILE and analyse it using standard SQL queries.

# 20th April 2009, 6:35 pm / evanweaver, introspection, memcached, mysql, peep, performance, scaling, sql, twitter

RubyForge: Starling. “Starling is a light-weight persistent queue server that speaks the MemCache protocol. It was built to drive Twitter’s backend, and is in production across Twitter’s cluster.”

# 11th January 2008, 9:47 pm / blaine-cook, memcached, message-queues, messaging, queue, ruby, rubyforge, starling, twitter