Lesson plan

Scribe (log server)

Scribe was a server for aggregating log data streamed in real-time from many servers. It was designed to be scalable, extensible without client-side modification, and robust to failure of the network or any specific machine. Scribe was developed at Facebook and released in 2008 as open source. Scribe servers are arranged in a directed graph, with each server knowing only about the next server in the graph. This network topology allows for adding extra layers of fan-in as a system grows, and batching messages before sending them between datacenters, without having any code that explicitly needs to understand datacenter topology, only a simple configuration. Scribe was designed to consider reliability but to not require heavyweight protocols and expansive disk usage. Scribe spools data to disk on any node to handle intermittent connectivity node failure, but doesn't sync a log file for every message. This creates a possibility of a small amount of data loss in the event of a crash or catastrophic hardware failure. However, this degree of reliability is often suitable for most Facebook use cases.

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Article summary

Scribe was a server for aggregating log data streamed in real-time from many servers. It was designed to be scalable, extensible without client-side modification, and robust to failure of the network or any specific machine. Scribe was developed at Facebook and released in 2008 as open source. Scribe servers are arranged in a directed graph, with each server knowing only about the next server in the graph. This network topology allows for adding extra layers of fan-in as a system grows, and batching messages before sending them between datacenters, without having any code that explicitly needs to understand datacenter topology, only a simple configuration. Scribe was designed to consider reliability but to not require heavyweight protocols and expansive disk usage. Scribe spools data to disk on any node to handle intermittent connectivity node failure, but doesn't sync a log file for every message. This creates a possibility of a small amount of data loss in the event of a crash or catastrophic hardware failure. However, this degree of reliability is often suitable for most Facebook use cases.

Key claims

  1. release date: 2008 — source: Wikipedia · confidence 0.95

Discussion questions

  1. Summarise the article in your own words. Which single claim would you verify first, and why?
  2. The record states that the release date is "2008". What evidence would count against this claim?
  3. Which claim in this article is most likely to be revised as the sources update? How would you check its current status?
  4. If two sources disagreed about one of these facts, what would you need in order to trust one over the other?

Bibliography

  1. Wikipedia https://en.wikipedia.org/w/index.php?oldid=1350672796

Key claims and bibliography are generated from the same tracked claims and sources as the article page.