Facebook uses MySQL extensively across its operations, complementing the use of HBase and Hadoop.
Its latest statistics include:
- 11.2 million row changes per second at peak. (inserts, updates, deletes on database whenever a user uploads a photo, makes a comment, or creates some other form of content).
- 2.5 billion rows read per second.
- 60.6 million selects per second - read - (the serving of data to users).
- 190 Gbps of network egress.
- Average response times 1.5 milliseconds (read) and 1.25 ms (write).
Twitter also uses MySQL as the "basic building block" for its data services. Its 'T-Bird' system records tweets and metadata, its 'Flock' system holds the social graph (user-to-user indexes), its 'T-Flock' system manages user timelines (user-to-tweet indexes, mentions, retweets) and its 'DM Bird' system manages direct messages.
Twitter's latest stats include:
- 200 million active users.
- Over 30 billion deliveries of 'Timelines' (refreshed user pages) per day.
- Over 500 million tweets per day.
- An average 7000 tweets per second, with regular peaks as high as 35,000.
- The record is a whopping 143,199 tweets in a second.
- During a peak, databases are hit with over one million requests per second.
Correction: The original article incorrectly stated that Mozilla had abandoned MariaDB for MySQL. The author has been informed that Mozilla is currently upgrading from MariaDB to MySQL 5.6. iTnews apologises for the error.