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Items tagged databases in Feb, 2010

Filters: Year: 2010 × Month: Feb × databases × Sorted by date


Johnny Cache. Clever twist on ORM-level caching for Django. Johnny Cache (great name) monkey-patches Django’s QuerySet classes and caches the result of every single SELECT query in memcached with an infinite expiry time. The cache key includes a “generation” ID for each dependent database table, and the generation is changed every single time a table is updated. For apps with infrequent writes, this strategy should work really well—but if a popular table is being updated constantly the cache will be all but useless. Impressively, the system is transaction-aware—cache entries created during a transaction are held in local memory and only pushed to memcached should the transaction complete successfully. # 28th February 2010, 10:55 pm

Redis Virtual Memory: the story and the code. Fascinating overview of the virtual memory feature coming to Redis 2.0, which will remove the requirement that all Redis data fit in RAM. Keys still stay in RAM, but rarely accessed values will be swapped to disk. 16 GB of RAM will be enough to hold 100 million keys, each with a value as large as you like. # 9th February 2010, 3:59 pm