The node.bandwidth.recovery.factor.write setting in Elasticsearch controls the proportion of a node's write bandwidth that can be used for recovery operations. This setting helps manage the balance between ongoing write operations and the recovery process, ensuring that recovery doesn't overwhelm the node's resources.
- Default value: 0.4 (40% of the node's write bandwidth)
- Possible values: 0.0 to 1.0 (0% to 100% of the node's write bandwidth)
- Recommendation: The default value is suitable for most scenarios, but you may need to adjust it based on your specific cluster requirements and hardware capabilities.
This setting was introduced in Elasticsearch 7.5.0 and is still applicable in current versions.
Example
To change the node.bandwidth.recovery.factor.write setting using the cluster settings API:
PUT _cluster/settings
{
"persistent": {
"node.bandwidth.recovery.factor.write": 0.5
}
}
This example increases the write bandwidth allocation for recovery operations to 50%. You might want to increase this value if you need faster recovery times and have sufficient write capacity. However, be cautious as this may impact the performance of regular write operations.
Common Issues and Misuses
- Setting the value too high can lead to degraded performance for regular write operations during recovery.
- Setting the value too low can significantly slow down the recovery process, potentially leading to prolonged cluster instability.
Do's and Don'ts
- Do monitor your cluster's performance when adjusting this setting.
- Do consider the trade-offs between recovery speed and regular operation performance.
- Don't set this value to 1.0 unless you're in an emergency situation and need the fastest possible recovery.
- Don't ignore this setting when planning for disaster recovery scenarios.
Frequently Asked Questions
Q: How does node.bandwidth.recovery.factor.write affect cluster stability?
A: This setting helps maintain cluster stability by balancing recovery operations with regular write operations. A well-tuned value ensures that recovery processes don't overwhelm the node, allowing it to continue serving regular requests effectively.
Q: Can changing node.bandwidth.recovery.factor.write impact indexing performance?
A: Yes, increasing this value allocates more bandwidth to recovery operations, which can potentially slow down regular indexing operations during recovery periods.
Q: Is it safe to change node.bandwidth.recovery.factor.write dynamically?
A: Yes, you can change this setting dynamically using the cluster settings API. However, it's advisable to make gradual changes and monitor the impact closely.
Q: How does this setting interact with node.bandwidth.recovery.factor.read?
A: While node.bandwidth.recovery.factor.write focuses on write operations during recovery, node.bandwidth.recovery.factor.read controls the read bandwidth allocation. Both settings work together to manage overall recovery performance.
Q: Should I adjust node.bandwidth.recovery.factor.write in a production environment?
A: It's generally safe to adjust this setting in production, but it should be done cautiously. Always test changes in a staging environment first and monitor the cluster closely after making adjustments in production.
