The http.client_stats.enabled setting in Elasticsearch controls whether HTTP client stats are collected and exposed. When enabled, it allows for monitoring and analysis of HTTP client performance within Elasticsearch.
Description
- Default value:
false - Possible values:
trueorfalse - Recommendation: Enable this setting if you need detailed HTTP client performance metrics, especially in environments with heavy HTTP client usage.
This setting is available starting from Elasticsearch version 7.7.0.
When enabled, Elasticsearch will collect statistics about HTTP client operations, including connection pool usage, request counts, and response times. These metrics can be valuable for diagnosing performance issues and optimizing HTTP client configurations.
Example
To enable HTTP client stats collection, you can use the cluster settings API:
PUT _cluster/settings
{
"persistent": {
"http.client_stats.enabled": true
}
}
Enabling this setting is useful when you want to:
- Monitor the performance of HTTP client operations
- Identify potential bottlenecks in HTTP client usage
- Optimize connection pool settings
The effect of enabling this setting is that Elasticsearch will start collecting and exposing HTTP client statistics, which can be accessed through various monitoring endpoints.
Common Issues and Misuses
- Enabling this setting in production environments without proper monitoring infrastructure may lead to unnecessary resource consumption.
- Misinterpreting the collected stats without considering the overall system context can lead to incorrect optimization decisions.
Do's and Don'ts
Do's:
- Enable this setting when troubleshooting HTTP client-related performance issues
- Use the collected stats in conjunction with other performance metrics for a comprehensive analysis
- Disable the setting when not actively monitoring to reduce overhead
Don'ts:
- Don't leave this setting enabled unnecessarily in production environments
- Don't rely solely on these stats for performance optimization without considering other factors
Frequently Asked Questions
Q: How does enabling http.client_stats.enabled affect Elasticsearch performance?
A: Enabling this setting has a minimal impact on performance. However, it does introduce a small overhead due to the collection and exposure of statistics. In most cases, this overhead is negligible.
Q: Where can I view the HTTP client stats once enabled?
A: You can access the HTTP client stats through the Nodes Stats API by making a GET request to /_nodes/stats/http_client.
Q: Can I enable http.client_stats.enabled for specific nodes only?
A: No, this setting is cluster-wide. When enabled, it applies to all nodes in the cluster.
Q: How often are the HTTP client stats updated?
A: The stats are updated in real-time as HTTP client operations occur. However, the frequency at which you retrieve these stats depends on your monitoring setup.
Q: Is it safe to enable http.client_stats.enabled in a production environment?
A: While it's generally safe, it's recommended to enable this setting only when needed for troubleshooting or performance analysis. For long-term production use, carefully consider the additional overhead and ensure you have proper monitoring in place to make use of the collected stats.
