minio/docs/compression

Compression Guide

MinIO server allows streaming compression to ensure efficient disk space usage. Compression happens inflight, i.e objects are compressed before being written to disk(s). MinIO uses klauspost/compress/s2 streaming compression due to its stability and performance.

This algorithm is specifically optimized for machine generated content. Write throughput is typically at least 300MB/s per CPU core. Decompression speed is typically at least 1GB/s. This means that in cases where raw IO is below these numbers compression will not only reduce disk usage but also help increase system throughput. Typically enabling compression on spinning disk systems will increase speed when the content can be compressed.

Get Started

1. Prerequisites

Install MinIO - MinIO Quickstart Guide.

2. Run MinIO with compression

Compression can be enabled by updating the compress config settings for MinIO server config. Config compress settings take extensions and mime-types to be compressed.

"compress": {
        "enabled": true,
        "extensions": [".txt",".log",".csv", ".json", ".tar"],
        "mime-types": ["text/*","application/json","application/xml"]
}

Since text, log, csv, json files are highly compressible, These extensions/mime-types are included by default for compression.

Having compression enabled and no extensions or mime types will attempt to compress anything that isn't explicitly known to be already compressed content. Settings for enabling compression on all content, except for types listed below:

"compress": {
        "enabled": true,
        "extensions": [],
        "mime-types": []
}

Incompressible content will be skipped with quite low CPU usage and storage overhead, typically at several GB/s.

To update the configuration, use mc admin config get command to get the current configuration file for the minio cluster in json format, and save it locally.

$ mc admin config get myminio/ > /tmp/myconfig

After updating the compression configuration in /tmp/myconfig , use mc admin config set command to update the configuration for the cluster. Restart the MinIO server to put the changes into effect.

$ mc admin config set myminio < /tmp/myconfig

The compression settings may also be set through environment variables. When set, environment variables override the defined compress config settings in the server config.

export MINIO_COMPRESS="true"
export MINIO_COMPRESS_EXTENSIONS=".pdf,.doc"
export MINIO_COMPRESS_MIMETYPES="application/pdf"

3. Note

• Already compressed objects are not fit for compression since they do not have compressible patterns. Such objects do not produce efficient LZ compression which is a fitness factor for a lossless data compression. Below is a list of common files and content-types which are not suitable for compression.

  • Extensions

    | gz | (GZIP) | bz2 | (BZIP2) | rar | (WinRAR) | zip | (ZIP) | 7z | (7-Zip) | xz | (LZMA) | mp4 | (MP4) | mkv | (MKV media) | mov | (MOV)

  • Content-Types

    | video/* | | audio/* | | application/zip | | application/x-gzip | | application/zip | | application/x-bz2 | | application/x-compress | | application/x-xz |

All files with these extensions and mime types are excluded from compression, even if compression is enabled for all types.

• MinIO does not support encryption with compression because compression and encryption together potentially enables room for side channel attacks like CRIME and BREACH

• MinIO does not support compression for Gateway (Azure/GCS/NAS) implementations.

To test the setup

To test this setup, practice put calls to the server using mc and use mc ls on the data directory to view the size of the object.

Explore Further

• Use mc with MinIO Server
• Use aws-cli with MinIO Server
• Use s3cmd with MinIO Server
• Use minio-go SDK with MinIO Server
• The MinIO documentation website