Redis history module

This module is intended to store history in Redis list with more fine-grained control over fields, optional compression and out-of-the box cluster support.

Storage model

This module stores keys as following:

  1. Get key prefix
  2. Append hostname
  3. Append _zst if history is compressed

There is also a special set where suffixes are stored, keyname for it is just key_prefix. For example, if there is a host example.local and it stores compressed history entries then it will save the following element if key_prefix set: example.local_zst.


Rspamd uses zstd compression. It is very fast for both compression and decompression and provides typically 50% compression rate for history elements. It should be used whenever you have enough computational power as it allows to reduce Redis memory footprint when storing elements.

WebUI support

Web Interface automatically recognises that history is stored in Redis and load it appropriately.


The configuration of this module is pretty straightforward (use local.d/history_redis.conf to define your own values:

servers =; # Redis server to store history
key_prefix = "rs_history"; # Default key name
nrows = 200; # Default rows limit
compress = true; # Use zstd compression when storing data in Redis
subject_privacy = false; # subject privacy is off