The http.compression setting in Elasticsearch controls whether HTTP responses should be compressed when sent from the cluster nodes. This setting helps reduce network bandwidth usage and can improve overall performance, especially when transferring large amounts of data.
Description
- Default value:
true - Possible values:
trueorfalse - Recommendation: Keep enabled unless there are specific reasons to disable it
The http.compression setting is enabled by default in Elasticsearch. When set to true, it allows Elasticsearch to compress HTTP responses using gzip compression, which can significantly reduce the amount of data transferred over the network.
Version Information
This setting has been available since early versions of Elasticsearch and continues to be supported in current versions.
Example
To disable HTTP compression using the cluster settings API:
PUT _cluster/settings
{
"persistent": {
"http.compression": false
}
}
Reason for changing: You might want to disable HTTP compression if you're experiencing issues with certain clients that don't support compressed responses or if you're doing network-level compression.
Effects of the change: Disabling compression will increase the amount of data transferred over the network but may reduce CPU usage on the Elasticsearch nodes.
Common Issues or Misuses
- Disabling compression without a valid reason, leading to increased network traffic
- Assuming compression is always beneficial without considering the trade-off between CPU usage and network bandwidth
Do's and Don'ts
Do's:
- Keep HTTP compression enabled for most use cases
- Monitor network traffic and CPU usage to ensure optimal performance
- Use client libraries that support compressed responses
Don'ts:
- Don't disable compression without a specific reason or thorough testing
- Don't assume compression will always improve performance in every scenario
Frequently Asked Questions
Q: Does enabling http.compression affect query performance?
A: Generally, http.compression has minimal impact on query performance. The slight increase in CPU usage for compression is often outweighed by the benefits of reduced network traffic.
Q: Can I selectively enable compression for specific types of requests?
A: The http.compression setting is a global setting. Elasticsearch doesn't provide built-in functionality to selectively compress responses based on request type.
Q: How much bandwidth can I save by enabling http.compression?
A: The amount of bandwidth saved depends on the nature of your data. Text-heavy responses can see compression ratios of 70-80%, while already-compressed data (like images) may see little benefit.
Q: Is http.compression safe to use with all Elasticsearch clients?
A: Most modern Elasticsearch clients support compressed responses. However, it's always a good idea to check your client library's documentation or test compression with your specific setup.
Q: Does http.compression work with HTTPS connections?
A: Yes, http.compression works with both HTTP and HTTPS connections. The compression occurs at the application level, independent of the transport layer security.
