Simon Willison’s Weblog

Items tagged caching in Mar

Filters: Month: Mar × caching ×

Reddit is now running on Cassandra. Migrating their persistent cache over from memcacheDB to Cassandra took one developer just ten days. # 13th March 2010, 12:14 am

Cache Machine: Automatic caching for your Django models. This is the third new ORM caching layer for Django I’ve seen in the past month! Cache Machine was developed for zamboni, the port of to Django. Caching is enabled using a model mixin class (to hook up some post_delete hooks) and a custom caching manager. Invalidation works by maintaining a “flush list” of dependent cache entries for each object—this is currently stored in memcached and hence has potential race conditions, but a comment in the source code suggests that this could be solved by moving to redis. # 11th March 2010, 7:35 pm

Announcing django-cachebot. The ORM caching space around Django is heating up. django-cachebot is used in production at and takes a more low level approach to cache invalidation than Johnny Cache, enabling you to specifically mark the querysets you wish to cache and providing some advanced options for cache invalidation. Unfortunately it currently relies on a patch to Django core to enable its own manager. # 6th March 2010, 12:48 pm

Is johnny-cache for you? “Using Johnny is really adopting a particular caching strategy. This strategy isn’t always a win; it can impact performance negatively”—but for a high percentage of Django sites there’s a very good chance it will be a net bonus. # 2nd March 2010, 11:44 am Johnny Cache. The blog entry announcing Johnny Cache (“a drop-in caching library/framework for Django that will cache all of your querysets forever in a consistent and safe manner”) to the world. # 1st March 2010, 11:48 am

How uses Varnish. Includes examples of the configuration options they use. # 2nd March 2009, 5:08 pm

hash. Douglas Crockford: “Any HTML tag that accepts a src= or href= attribute should also be allowed to take a hash= attribute”—to protect against file tampering and (more importantly) provide a truly robust caching mechanism. # 30th March 2008, 6:34 pm

Consistent Hashing. Beautifully clear explanation of consistent hashing, a simple technique that allows you to add new caching servers to a cluster without re-hashing your keys and hence invalidating all of your caches. # 18th March 2008, 1 am

Two data streams for a happy website. Useful architectural concept for scaling: keep user-specific and generic data separate from the start, in recognition of their different caching and partitioning constraints. # 4th March 2008, 4:40 am