ESA compresses static resources to reduce data transfer sizes and improve page load speeds.
Introduction
ESA provides three compression methods: Gzip, Brotli, and Zstd. They differ in compression efficiency, decompression speed, and compatibility, making them suitable for different scenarios.
Compression type | Compression efficiency | Compatibility | Use case |
Gzip | Fast compression, medium decompression speed | High | General web services |
Brotli | Slow compression, high decompression speed | Medium | Static resource optimization |
Zstd | Very fast compression, very fast decompression | Low | Real-time stream data processing |
Notes
If you enable Gzip, Brotli, and Zstd at the same time, they are applied in the following order: Zstd > Brotli > Gzip.
ESA supports compression for the following file types:
text/xml,text/plain,text/css,application/javascript,application/x-javascript,application/rss+xml,text/javascript,image/tiff,image/svg+xml,application/json, andapplication/xml.
Cases where compression rules do not take effect
Compression rules are not applied in certain cases because of conflicting settings on the origin server or client.
For origin server
Gzip or Brotli compression is applied only to files from the origin server that are between 1 KB and 10 MB. Files outside this size range are not compressed.
If the response from the origin server includes the
Content-Encodingheader, ESA does not apply compression.If the response from the origin server contains the
cache-control: no-transformHTTP header, ESA does not apply compression.
For client
If a client does not support the configured compression algorithm, the response is not compressed. Client support is indicated by the Accept-Encoding request header.
Procedure
In the ESA console, select Websites, and then click the target site in the Website column.
In the navigation pane on the left, choose .
Select the Speed Optimization tab. Then, turn on the Gzip, Brotli, and Zstd switches as needed.
