Configurable retention policy for index failures in MongoDB

We are running multiple graylog clusters with very high throughput. Recently, we noticed heavy load on the MongoDB for graylog. Reason being a high number of index failures.
As graylog is usually light on MongoDB and so, it is a small cluster.
- Is there any way to disable or control these messages to avoid load on MongoDB?
- Is there any retention policy for index failure messages in MongoDB?

I searched the documentation, but unable to find any solution.
## Expected Behavior

Ability to control / disable and have retention policy for graylog index failures on MongoDB.
## Current Behavior

High load on MongoDB due to index failures.
## Possible Solution

Configurable parameters to control / disable and have retention policy for graylog index failures on MongoDB.
## Your Environment
- Graylog Version: 2.1.0
- Elasticsearch Version: 2.4.0
- MongoDB Version: latest
- Operating System: ubuntu 14.04
- Browser version: latest