From 953df2ad88fb9fc7d1a67966c79980136321119d Mon Sep 17 00:00:00 2001
From: Andrew Morgan <1342360+anoadragon453@users.noreply.github.com>
Date: Thu, 11 Aug 2022 14:06:09 +0100
Subject: [PATCH] Add note to `redaction_retention_period` documentation
 mentioning that event purging runs at most every 5m (#13492)

---
 changelog.d/13492.doc                            | 1 +
 docs/usage/configuration/config_documentation.md | 4 ++++
 2 files changed, 5 insertions(+)
 create mode 100644 changelog.d/13492.doc

diff --git a/changelog.d/13492.doc b/changelog.d/13492.doc
new file mode 100644
index 000000000..fc4850d55
--- /dev/null
+++ b/changelog.d/13492.doc
@@ -0,0 +1 @@
+Document that event purging related to the `redaction_retention_period` config option is executed only every 5 minutes.
diff --git a/docs/usage/configuration/config_documentation.md b/docs/usage/configuration/config_documentation.md
index 2af32a615..bc3d2bec6 100644
--- a/docs/usage/configuration/config_documentation.md
+++ b/docs/usage/configuration/config_documentation.md
@@ -759,6 +759,10 @@ allowed_avatar_mimetypes: ["image/png", "image/jpeg", "image/gif"]
 How long to keep redacted events in unredacted form in the database. After
 this period redacted events get replaced with their redacted form in the DB.
 
+Synapse will check whether the rentention period has concluded for redacted
+events every 5 minutes. Thus, even if this option is set to `0`, Synapse may
+still take up to 5 minutes to purge redacted events from the database.
+
 Defaults to `7d`. Set to `null` to disable.
 
 Example configuration: