On: Notes from a production MongoDB deployment

[rubyrescue]

If you suffer a power loss and/or MongoDB exits uncleanly then you will need to repair your database.... it involves MongoDB going through every single document and rebuilding it. When you have databases at the size of ours, this would take hours.

- that seems really scary

[spudlyo → rubyrescue]

Scary yet familiar. I work with many databases that have large MyISAM tables, which is essentially the same situation.

[dmerr → rubyrescue]

http://blog.mongodb.org/post/381927266/what-about-durability

[jbellis → rubyrescue]

Yes, and if you run a cluster long enough you WILL suffer unplanned power loss. Usually due to human error of one sort or another. It's basically impossible to eliminate entirely.