The node.bandwidth.recovery.operator.factor.max_overcommit setting in Elasticsearch controls the maximum overcommitment factor for the recovery operator's bandwidth allocation. This setting helps manage the balance between recovery speed and overall cluster performance during shard recovery operations.
- Default Value: 2.0
- Possible Values: Any positive float value
- Recommendation: The default value is suitable for most scenarios, but it can be adjusted based on specific cluster needs and network capabilities.
This setting determines how much the recovery operator can exceed its allocated bandwidth. A value of 2.0 means that the operator can use up to twice its allocated bandwidth for short periods, allowing for faster recoveries when extra bandwidth is available.
This setting was introduced in Elasticsearch 7.13.0.
Example Usage
To change this setting using the cluster settings API:
PUT _cluster/settings
{
"transient": {
"node.bandwidth.recovery.operator.factor.max_overcommit": 2.5
}
}
Increasing this value can lead to faster shard recoveries when extra bandwidth is available. However, it may also cause more network congestion during peak recovery periods.
Common Issues and Misuses
- Setting this value too high can lead to network saturation and impact other cluster operations.
- Very low values may unnecessarily slow down recovery processes, even when bandwidth is available.
Do's and Don'ts
- Do monitor network usage and recovery times when adjusting this setting.
- Do consider the impact on other cluster operations when increasing this value.
- Don't set this value excessively high without understanding your network capabilities.
- Don't ignore this setting when experiencing slow recoveries or network issues during recovery operations.
Frequently Asked Questions
Q: How does this setting affect shard recovery speed?
A: This setting allows the recovery process to temporarily use more bandwidth than allocated, potentially speeding up shard recoveries when extra network capacity is available.
Q: Can increasing this value cause network issues?
A: Yes, setting it too high can lead to network congestion and affect other cluster operations, especially during peak recovery periods.
Q: Should I change this setting from its default value?
A: The default value is suitable for most scenarios. Only consider changing it if you have specific recovery performance needs and understand your network capabilities.
Q: How does this setting interact with other bandwidth-related settings?
A: This setting works in conjunction with other bandwidth settings to manage recovery operations. It specifically allows for short-term overcommitment of the allocated bandwidth.
Q: Can this setting be changed dynamically?
A: Yes, this setting can be updated dynamically using the cluster settings API without requiring a cluster restart.
