Tag Archives: nosql

MongoDB Monitoring: Keep in it RAM

Posted on December 13, 2010 by David Mytton

There are a number of built in tools and commands which can be used to get important information from MongoDB but because it is relatively new, it can be difficult to know what you need to be doing from an … Continue reading →

Posted in MongoDB, Server Monitoring | Tagged , , , , , | Comments Off

Reclaiming memory from MongoDB indexes

Posted on December 10, 2010 by David Mytton

As of the current version of MongoDB (1.7.3), deleting data does not compact indexes and their use of RAM. Indeed, this was the root cause of the problem Foursquare experienced several months ago. This means that once your indexes exceed … Continue reading →

Posted in MongoDB | Tagged , | 6 Comments

On shortened field names in MongoDB

Posted on October 23, 2010 by David Mytton

Last night we got almost 10k unique visitors in just a few hours because of a post disputing a minor point of a post I wrote in July 2009. The problem was with the reduction of field names in our … Continue reading →

Posted in MongoDB, Programming, Technical | Tagged , , , , , | 13 Comments

When would ever need more than 7 replica set members?

Posted on October 13, 2010 by David Mytton

MongoDB supports the concept of replica sets which is like master/slave, but any member can become master automatically if the current master fails. It allows for automated, near instant failover. We’re using it live in production and each of our … Continue reading →

Posted in MongoDB, Servers, sysadmin, Technical | Tagged , , , , | 1 Comment

Automating partitioning, sharding and failover with MongoDB

Posted on August 3, 2010 by David Mytton

Two of the most eagerly anticipated features for MongoDB, the database backend we use for our server monitoring service, Server Density, are auto sharding and replica sets. Sharding will allow us to let MongoDB handle distribution of data across any … Continue reading →

Posted in MongoDB, Programming, Servers, sysadmin, Technical | Tagged , , , , , , , | 18 Comments

Choosing a non-relational database; why we migrated from MySQL to MongoDB

Posted on July 25, 2009 by David Mytton

Update 23 Oct 2010: A discussion about the value of shortened field names has generated a lot of traffic to this post over the last 24 hours. A response has been posted here. Update 28 Feb 2010: A followup was … Continue reading →

Posted in MongoDB, MySQL, Programming, Server Density, Servers, Technical | Tagged , , , , , | 116 Comments