Simon Willison’s Weblog

Blogmarks tagged scaling in Jan

Filters: Type: blogmark × Month: Jan × scaling ×


Serving 100µs reads with 100% availability (via) Fascinating use-case for SQLite from Segment: they needed a massively replicated configuration database across all of their instances that process streaming data. They chose to make the configuration available as a ~50GB SQLite database file mirrored to every instance, meaning lookups against that data could complete in microseconds. Changes to the central MySQL configuration store are pulled every 2-3 seconds, resulting in a trade-off of consistency for availability which fits their use-case just fine. # 10th January 2020, 5:15 am

Sharding Counters on Google App Engine. “While the datastore for App Engine scales to support a huge number of entities it is important to note that you can only expect to update any single entity, or entity-group, about five times a second”. This article explains a technique for sharding writes across multiple counters in detail, including a way to keep a memcache counter updated at the same time for faster reads. # 27th January 2009, 8:27 pm

Project Voldemort. Yet Another “big, distributed, persistent, fault-tolerant hash table”—this time from LinkedIn, released under the Apache 2.0 license. The approach to consistency is interesting—instead of using distributed transactions, they use versioning and “resolve inconsistencies at read time”. It also uses consistent hashing (as seen in libketama) to select servers. The design document has lots more information. # 17th January 2009, 7:45 pm

New Gearman Server & Library in C, MySQL UDFs. Gearman, the job queue written for LiveJournal and now used by Digg and Yahoo!, has been rewritten in C. Looks like a good candidate for an easily configured lightweight message queue. Also includes hooks for writing MySQL functions that can interact with queues. # 13th January 2009, 4:41 pm

MemcacheDB. A server that speaks the memcache protocol but uses Berkeley DB for reliable persistent storage. Speedy: 20,000 writes/second and 60,000+ reads/second. Includes a full replication mechanism (with custom memcache protocol commands) based on Berkeley DB’s. # 5th January 2009, 12:37 pm

Inside MySpace.com. Case study of scaling against a network effect. Includes pretty honest coverage of the mistakes made along the way, although the article was put together second hand from conference presentations rather than from interviews. # 17th January 2007, 9:18 am

New Technorati Infrastructure beta test! (via) It certainly feels faster # 20th January 2004, 10:36 pm