From bf3677a9b5a47fa1433bea1ce1e6c4ca2174c67f Mon Sep 17 00:00:00 2001
From: Aine <aine@etke.cc>
Date: Fri, 10 Mar 2023 23:48:43 +0200
Subject: [PATCH 01/10] add synapse_auto_compressor

---
 README.md                                     |  1 +
 ...guring-playbook-synapse-auto-compressor.md | 36 +++++++++++++
 playbooks/matrix.yml                          |  1 +
 .../defaults/main.yml                         | 51 ++++++++++++++++++
 .../tasks/install.yml                         | 53 +++++++++++++++++++
 .../tasks/main.yml                            | 17 ++++++
 .../tasks/uninstall.yml                       | 29 ++++++++++
 .../matrix-synapse-auto-compressor.service.j2 | 35 ++++++++++++
 .../matrix-synapse-auto-compressor.timer.j2   |  9 ++++
 9 files changed, 232 insertions(+)
 create mode 100644 docs/configuring-playbook-synapse-auto-compressor.md
 create mode 100644 roles/custom/matrix-synapse-auto-compressor/defaults/main.yml
 create mode 100644 roles/custom/matrix-synapse-auto-compressor/tasks/install.yml
 create mode 100644 roles/custom/matrix-synapse-auto-compressor/tasks/main.yml
 create mode 100644 roles/custom/matrix-synapse-auto-compressor/tasks/uninstall.yml
 create mode 100644 roles/custom/matrix-synapse-auto-compressor/templates/matrix-synapse-auto-compressor.service.j2
 create mode 100644 roles/custom/matrix-synapse-auto-compressor/templates/matrix-synapse-auto-compressor.timer.j2

diff --git a/README.md b/README.md
index 185c4085..ff93cd1f 100644
--- a/README.md
+++ b/README.md
@@ -163,6 +163,7 @@ Various services that don't fit any other category.
 | Name | Default? | Description | Documentation |
 | ---- | -------- | ----------- | ------------- |
 | [sliding-sync](https://github.com/matrix-org/sliding-sync)| x | Sliding Sync support for clients which require it (e.g. Element X) | [Link](docs/configuring-playbook-sliding-sync-proxy.md) |
+| [synapse_auto_compressor](https://github.com/matrix-org/rust-synapse-compress-state/#automated-tool-synapse_auto_compressor) | x | A cli tool that automatically compresses `state_groups` database table in background. | [Link](docs/configuring-playbook-synapse-auto-compressor.md) |
 | [synapse-simple-antispam](https://github.com/t2bot/synapse-simple-antispam) (advanced) | x | A spam checker module | [Link](docs/configuring-playbook-synapse-simple-antispam.md) |
 | [Matrix Corporal](https://github.com/devture/matrix-corporal) (advanced) | x | Reconciliator and gateway for a managed Matrix server | [Link](docs/configuring-playbook-matrix-corporal.md) |
 | [Etherpad](https://etherpad.org) | x | An open source collaborative text editor | [Link](docs/configuring-playbook-etherpad.md) |
diff --git a/docs/configuring-playbook-synapse-auto-compressor.md b/docs/configuring-playbook-synapse-auto-compressor.md
new file mode 100644
index 00000000..cd6079ca
--- /dev/null
+++ b/docs/configuring-playbook-synapse-auto-compressor.md
@@ -0,0 +1,36 @@
+# Setting up synapse_auto_compressor
+
+The playbook can install and configure [synapse_auto_compressor](https://github.com/matrix-org/rust-synapse-compress-state/#automated-tool-synapse_auto_compressor) for you.
+
+It's a cli tool that automatically compresses `state_groups` database table in background.
+
+See the project's [documentation](https://github.com/matrix-org/rust-synapse-compress-state/#automated-tool-synapse_auto_compressor) to learn what it does and why it might be useful to you.
+
+
+## Adjusting the playbook configuration
+
+Add the following configuration to your `inventory/host_vars/matrix.DOMAIN/vars.yml` file:
+
+```yaml
+matrix_synapse_auto_compressor_enabled: true
+```
+
+
+## Installing
+
+After configuring the playbook, run the [installation](installing.md) command again:
+
+```
+ansible-playbook -i inventory/hosts setup.yml --tags=setup-all,start
+```
+
+
+## Usage
+
+After installation, synapse_auto_compressor will run automatically every day by the defined schedule
+
+## Manually start the tool
+
+For testing your setup it can be helpful to not wait until 00:00. If you want to run the tool immediately, log onto the server
+and run `systemctl start matrix-synapse-auto-compressor`. This will not return until the run is done, so possibly a long time.
+Consider using [tmux](https://en.wikipedia.org/wiki/Tmux) if your SSH connection is unstable.
diff --git a/playbooks/matrix.yml b/playbooks/matrix.yml
index a2b7f2b8..b8964aa5 100755
--- a/playbooks/matrix.yml
+++ b/playbooks/matrix.yml
@@ -84,6 +84,7 @@
     - custom/matrix-cactus-comments
     - custom/matrix-rageshake
     - custom/matrix-synapse
+    - custom/matrix-synapse-auto-compressor
     - custom/matrix-synapse-reverse-proxy-companion
     - custom/matrix-dendrite
     - custom/matrix-conduit
diff --git a/roles/custom/matrix-synapse-auto-compressor/defaults/main.yml b/roles/custom/matrix-synapse-auto-compressor/defaults/main.yml
new file mode 100644
index 00000000..d24564ce
--- /dev/null
+++ b/roles/custom/matrix-synapse-auto-compressor/defaults/main.yml
@@ -0,0 +1,51 @@
+---
+# synapse_auto_compressor tool
+# Project source code URL: https://github.com/matrix-org/rust-synapse-compress-state
+
+matrix_synapse_auto_compressor_enabled: false
+
+matrix_synapse_auto_compressor_container_image_self_build: false
+matrix_synapse_auto_compressor_container_repo: "https://gitlab.com/etke.cc/rust-synapse-compress-state.git"
+matrix_synapse_auto_compressor_container_repo_version: "{{ 'main' if matrix_synapse_auto_compressor_version == 'latest' else matrix_synapse_auto_compressor_version }}"
+matrix_synapse_auto_compressor_container_src_files_path: "{{ matrix_synapse_auto_compressor_base_path }}"
+
+matrix_synapse_auto_compressor_version: v0.1.3
+matrix_synapse_auto_compressor_container_image: "{{ matrix_synapse_auto_compressor_container_image_name_prefix }}etke.cc/rust-synapse-compress-state:{{ matrix_synapse_auto_compressor_version }}"
+matrix_synapse_auto_compressor_container_image_name_prefix: "{{ 'localhost/' if matrix_synapse_auto_compressor_container_image_self_build else 'registry.gitlab.com/' }}"
+matrix_synapse_auto_compressor_container_image_force_pull: "{{ matrix_synapse_auto_compressor_container_image.endswith(':latest') }}"
+
+matrix_synapse_auto_compressor_base_path: "{{ matrix_base_data_path }}/synapse-auto-compressor"
+
+# A list of extra arguments to pass to the container
+matrix_synapse_auto_compressor_container_extra_arguments: []
+
+# List of systemd services that matrix-synapse-auto-compressor.service depends on
+matrix_synapse_auto_compressor_systemd_required_services_list: ['docker.service']
+
+# List of systemd services that matrix-synapse-auto-compressor.service wants
+matrix_synapse_auto_compressor_systemd_wanted_services_list: []
+
+matrix_synapse_auto_compressor_database_username: 'synapse'
+matrix_synapse_auto_compressor_database_password: 'some-password'
+matrix_synapse_auto_compressor_database_hostname: ''
+matrix_synapse_auto_compressor_database_port: 5432
+matrix_synapse_auto_compressor_database_name: 'synapse'
+
+# connection string to synapse database (postgres only)
+matrix_synapse_auto_compressor_synapse_database: 'postgres://{{ matrix_synapse_auto_compressor_database_username }}:{{ matrix_synapse_auto_compressor_database_password }}@{{ matrix_synapse_auto_compressor_database_hostname }}:{{ matrix_synapse_auto_compressor_database_port }}/{{ matrix_synapse_auto_compressor_database_name }}'
+
+# systemd calendar configuration for the compressor job
+matrix_synapse_auto_compressor_calendar: "*-*-* 00:00:00"
+
+# The number of state groups to work on at once.
+# All of the entries from state_groups_state are requested from the database for state groups that are worked on.
+# Therefore small chunk sizes may be needed on machines with low memory.
+# Note: if the compressor fails to find space savings on the chunk as a whole
+# (which may well happen in rooms with lots of backfill in) then the entire chunk is skipped.
+matrix_synapse_auto_compressor_chunk_size: 500
+
+# CHUNKS_TO_COMPRESS chunks of size CHUNK_SIZE will be compressed.
+# The higher this number is set to, the longer the compressor will run for.
+matrix_synapse_auto_compressor_chunks_to_compress: 100
+
+matrix_synapse_auto_compressor_command: "synapse_auto_compressor -p {{ matrix_synapse_auto_compressor_synapse_database }} -c {{ matrix_synapse_auto_compressor_chunk_size }} -n {{ matrix_synapse_auto_compressor_chunks_to_compress }}"
diff --git a/roles/custom/matrix-synapse-auto-compressor/tasks/install.yml b/roles/custom/matrix-synapse-auto-compressor/tasks/install.yml
new file mode 100644
index 00000000..ec825b13
--- /dev/null
+++ b/roles/custom/matrix-synapse-auto-compressor/tasks/install.yml
@@ -0,0 +1,53 @@
+---
+- name: Ensure synapse-auto-compressor paths exist
+  ansible.builtin.file:
+    path: "{{ matrix_synapse_auto_compressor_container_src_files_path }}"
+    state: directory
+    mode: 0750
+    owner: "{{ matrix_user_username }}"
+    group: "{{ matrix_user_groupname }}"
+  when: matrix_synapse_auto_compressor_container_image_self_build | bool
+
+- name: Ensure synapse-auto-compressor image is pulled
+  community.docker.docker_image:
+    name: "{{ matrix_synapse_auto_compressor_container_image }}"
+    source: "{{ 'pull' if ansible_version.major > 2 or ansible_version.minor > 7 else omit }}"
+    force_source: "{{ matrix_synapse_auto_compressor_container_image_force_pull if ansible_version.major > 2 or ansible_version.minor >= 8 else omit }}"
+    force: "{{ omit if ansible_version.major > 2 or ansible_version.minor >= 8 else matrix_synapse_auto_compressor_container_image_force_pull }}"
+  when: "not matrix_synapse_auto_compressor_container_image_self_build | bool"
+  register: result
+  retries: "{{ devture_playbook_help_container_retries_count }}"
+  delay: "{{ devture_playbook_help_container_retries_delay }}"
+  until: result is not failed
+
+- name: Ensure synapse-auto-compressor repository is present on self-build
+  ansible.builtin.git:
+    repo: "{{ matrix_synapse_auto_compressor_container_repo }}"
+    version: "{{ matrix_synapse_auto_compressor_container_repo_version }}"
+    dest: "{{ matrix_synapse_auto_compressor_container_src_files_path }}"
+    force: "yes"
+  become: true
+  become_user: "{{ matrix_user_username }}"
+  register: matrix_synapse_auto_compressor_git_pull_results
+  when: "matrix_synapse_auto_compressor_container_image_self_build | bool"
+
+- name: Ensure synapse-auto-compressor image is built
+  community.docker.docker_image:
+    name: "{{ matrix_synapse_auto_compressor_container_image }}"
+    source: build
+    force_source: "{{ matrix_synapse_auto_compressor_git_pull_results.changed if ansible_version.major > 2 or ansible_version.minor >= 8 else omit }}"
+    force: "{{ omit if ansible_version.major > 2 or ansible_version.minor >= 8 else matrix_mailer_git_pull_results.changed }}"
+    build:
+      dockerfile: Dockerfile
+      path: "{{ matrix_synapse_auto_compressor_container_src_files_path }}"
+      pull: true
+  when: "matrix_synapse_auto_compressor_container_image_self_build | bool"
+
+- name: Ensure matrix-synapse-auto-compressor systemd service and timer are installed
+  ansible.builtin.template:
+    src: "{{ role_path }}/templates/matrix-synapse-auto-compressor.{{ item }}.j2"
+    dest: "{{ devture_systemd_docker_base_systemd_path }}/matrix-synapse-auto-compressor.{{ item }}"
+    mode: 0644
+  with_items:
+    - service
+    - timer
diff --git a/roles/custom/matrix-synapse-auto-compressor/tasks/main.yml b/roles/custom/matrix-synapse-auto-compressor/tasks/main.yml
new file mode 100644
index 00000000..b3549bd6
--- /dev/null
+++ b/roles/custom/matrix-synapse-auto-compressor/tasks/main.yml
@@ -0,0 +1,17 @@
+---
+
+- block:
+    - when: matrix_synapse_auto_compressor_enabled | bool
+      ansible.builtin.include_tasks: "{{ role_path }}/tasks/install.yml"
+  tags:
+    - setup-all
+    - setup-synapse-auto-compressor
+    - install-all
+    - install-synapse-auto-compressor
+
+- block:
+    - when: not matrix_synapse_auto_compressor_enabled | bool
+      ansible.builtin.include_tasks: "{{ role_path }}/tasks/uninstall.yml"
+  tags:
+    - setup-all
+    - setup-synapse-auto-compressor
diff --git a/roles/custom/matrix-synapse-auto-compressor/tasks/uninstall.yml b/roles/custom/matrix-synapse-auto-compressor/tasks/uninstall.yml
new file mode 100644
index 00000000..075f3c10
--- /dev/null
+++ b/roles/custom/matrix-synapse-auto-compressor/tasks/uninstall.yml
@@ -0,0 +1,29 @@
+---
+- name: Check existence of matrix-synapse-auto-compressor service
+  ansible.builtin.stat:
+    path: "{{ devture_systemd_docker_base_systemd_path }}/matrix-synapse-auto-compressor.service"
+  register: matrix_synapse_auto_compressor_service_stat
+
+- when: matrix_synapse_auto_compressor_service_stat.stat.exists | bool
+  block:
+    - name: Ensure matrix-synapse-auto-compressor is stopped
+      ansible.builtin.service:
+        name: matrix-synapse-auto-compressor
+        state: stopped
+        enabled: false
+        daemon_reload: true
+
+    - name: Ensure matrix-synapse-auto-compressor.service doesn't exist
+      ansible.builtin.file:
+        path: "{{ devture_systemd_docker_base_systemd_path }}/matrix-synapse-auto-compressor.service"
+        state: absent
+
+    - name: Ensure matrix-synapse-auto-compressor.timer doesn't exist
+      ansible.builtin.file:
+        path: "{{ devture_systemd_docker_base_systemd_path }}/matrix-synapse-auto-compressor.timer"
+        state: absent
+
+    - name: Ensure Matrix synapse-auto-compressor paths don't exist
+      ansible.builtin.file:
+        path: "{{ matrix_synapse_auto_compressor_base_path }}"
+        state: absent
diff --git a/roles/custom/matrix-synapse-auto-compressor/templates/matrix-synapse-auto-compressor.service.j2 b/roles/custom/matrix-synapse-auto-compressor/templates/matrix-synapse-auto-compressor.service.j2
new file mode 100644
index 00000000..02aef84b
--- /dev/null
+++ b/roles/custom/matrix-synapse-auto-compressor/templates/matrix-synapse-auto-compressor.service.j2
@@ -0,0 +1,35 @@
+#jinja2: lstrip_blocks: "True"
+[Unit]
+Description=Synapse State Auto Compressor
+{% for service in matrix_synapse_auto_compressor_systemd_required_services_list %}
+Requires={{ service }}
+After={{ service }}
+{% endfor %}
+{% for service in matrix_synapse_auto_compressor_systemd_wanted_services_list %}
+Wants={{ service }}
+{% endfor %}
+DefaultDependencies=no
+
+[Service]
+Type=oneshot
+Environment="HOME={{ devture_systemd_docker_base_systemd_unit_home_path }}"
+ExecStartPre=-{{ devture_systemd_docker_base_host_command_sh }} -c '{{ devture_systemd_docker_base_host_command_docker }} kill matrix-synapse-auto-compressor 2>/dev/null || true'
+ExecStartPre=-{{ devture_systemd_docker_base_host_command_sh }} -c '{{ devture_systemd_docker_base_host_command_docker }} rm matrix-synapse-auto-compressor 2>/dev/null || true'
+ExecStart={{ devture_systemd_docker_base_host_command_docker }} run --rm --name matrix-synapse-auto-compressor \
+			--log-driver=none \
+			--cap-drop=ALL \
+			--read-only \
+			--user={{ matrix_user_uid }}:{{ matrix_user_gid }} \
+			--network={{ matrix_docker_network }} \
+			{% for arg in matrix_synapse_auto_compressor_container_extra_arguments %}
+			{{ arg }} \
+			{% endfor %}
+			{{ matrix_synapse_auto_compressor_container_image }} \
+			{{ matrix_synapse_auto_compressor_command }}
+
+ExecStop=-{{ devture_systemd_docker_base_host_command_sh }} -c '{{ devture_systemd_docker_base_host_command_docker }} kill matrix-synapse-auto-compressor 2>/dev/null || true'
+ExecStop=-{{ devture_systemd_docker_base_host_command_sh }} -c '{{ devture_systemd_docker_base_host_command_docker }} rm matrix-synapse-auto-compressor 2>/dev/null || true'
+SyslogIdentifier=matrix-synapse-auto-compressor
+
+[Install]
+WantedBy=multi-user.target
diff --git a/roles/custom/matrix-synapse-auto-compressor/templates/matrix-synapse-auto-compressor.timer.j2 b/roles/custom/matrix-synapse-auto-compressor/templates/matrix-synapse-auto-compressor.timer.j2
new file mode 100644
index 00000000..1d7b16d3
--- /dev/null
+++ b/roles/custom/matrix-synapse-auto-compressor/templates/matrix-synapse-auto-compressor.timer.j2
@@ -0,0 +1,9 @@
+[Unit]
+Description=Synapse State Auto Compressor Timer
+
+[Timer]
+Unit=matrix-synapse-auto-compressor.service
+OnCalendar={{ matrix_synapse_auto_compressor_calendar }}
+
+[Install]
+WantedBy=timers.target

From 43ae0b2943e24444369c9f6f534f5890238c9cf7 Mon Sep 17 00:00:00 2001
From: Slavi Pantaleev <slavi@devture.com>
Date: Sun, 12 Mar 2023 09:44:43 +0200
Subject: [PATCH 02/10] Minor rewording

---
 docs/configuring-playbook-synapse-auto-compressor.md | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/docs/configuring-playbook-synapse-auto-compressor.md b/docs/configuring-playbook-synapse-auto-compressor.md
index cd6079ca..108b6a11 100644
--- a/docs/configuring-playbook-synapse-auto-compressor.md
+++ b/docs/configuring-playbook-synapse-auto-compressor.md
@@ -2,7 +2,7 @@
 
 The playbook can install and configure [synapse_auto_compressor](https://github.com/matrix-org/rust-synapse-compress-state/#automated-tool-synapse_auto_compressor) for you.
 
-It's a cli tool that automatically compresses `state_groups` database table in background.
+It's a CLI tool that automatically compresses Synapse's `state_groups` database table in the background.
 
 See the project's [documentation](https://github.com/matrix-org/rust-synapse-compress-state/#automated-tool-synapse_auto_compressor) to learn what it does and why it might be useful to you.
 
@@ -27,10 +27,10 @@ ansible-playbook -i inventory/hosts setup.yml --tags=setup-all,start
 
 ## Usage
 
-After installation, synapse_auto_compressor will run automatically every day by the defined schedule
+After installation, `synapse_auto_compressor` will run automatically every day at `00:00:00` (as defined in `matrix_synapse_auto_compressor_calendar` by default).
 
 ## Manually start the tool
 
 For testing your setup it can be helpful to not wait until 00:00. If you want to run the tool immediately, log onto the server
-and run `systemctl start matrix-synapse-auto-compressor`. This will not return until the run is done, so possibly a long time.
+and run `systemctl start matrix-synapse-auto-compressor`. Running this command will not return control to your terminal until the compression run is done, which may take a long time.
 Consider using [tmux](https://en.wikipedia.org/wiki/Tmux) if your SSH connection is unstable.

From b28d779c6cc8cc4f80a48295ebd0a93cc63311c5 Mon Sep 17 00:00:00 2001
From: Slavi Pantaleev <slavi@devture.com>
Date: Sun, 12 Mar 2023 09:48:46 +0200
Subject: [PATCH 03/10] Add matrix-synapse-auto-compressor section in
 group_vars/matrix_servers

---
 group_vars/matrix_servers                      | 18 ++++++++++++++++++
 .../defaults/main.yml                          |  3 ++-
 2 files changed, 20 insertions(+), 1 deletion(-)

diff --git a/group_vars/matrix_servers b/group_vars/matrix_servers
index 85fbfd2a..6a90114f 100755
--- a/group_vars/matrix_servers
+++ b/group_vars/matrix_servers
@@ -3326,6 +3326,24 @@ matrix_synapse_app_service_config_files_auto: "{{ matrix_homeserver_app_service_
 #
 ######################################################################
 
+
+######################################################################
+#
+# matrix-synapse-auto-compressor
+#
+######################################################################
+
+matrix_synapse_auto_compressor_enabled: false
+
+matrix_synapse_auto_compressor_container_image_self_build: "{{ matrix_architecture not in ['arm32', 'arm64', 'amd64'] }}"
+
+######################################################################
+#
+# /matrix-synapse-auto-compressor
+#
+######################################################################
+
+
 ######################################################################
 #
 # matrix-synapse-reverse-proxy-companion
diff --git a/roles/custom/matrix-synapse-auto-compressor/defaults/main.yml b/roles/custom/matrix-synapse-auto-compressor/defaults/main.yml
index d24564ce..99fb272f 100644
--- a/roles/custom/matrix-synapse-auto-compressor/defaults/main.yml
+++ b/roles/custom/matrix-synapse-auto-compressor/defaults/main.yml
@@ -1,8 +1,9 @@
 ---
+
 # synapse_auto_compressor tool
 # Project source code URL: https://github.com/matrix-org/rust-synapse-compress-state
 
-matrix_synapse_auto_compressor_enabled: false
+matrix_synapse_auto_compressor_enabled: true
 
 matrix_synapse_auto_compressor_container_image_self_build: false
 matrix_synapse_auto_compressor_container_repo: "https://gitlab.com/etke.cc/rust-synapse-compress-state.git"

From ca69fce64824548d240f69b375f1d6f51cba41b1 Mon Sep 17 00:00:00 2001
From: Slavi Pantaleev <slavi@devture.com>
Date: Sun, 12 Mar 2023 09:55:32 +0200
Subject: [PATCH 04/10] Add missing group vars for
 matrix-synapse-auto-compressor

---
 group_vars/matrix_servers | 16 +++++++++++++++-
 1 file changed, 15 insertions(+), 1 deletion(-)

diff --git a/group_vars/matrix_servers b/group_vars/matrix_servers
index 6a90114f..5712b037 100755
--- a/group_vars/matrix_servers
+++ b/group_vars/matrix_servers
@@ -3333,9 +3333,23 @@ matrix_synapse_app_service_config_files_auto: "{{ matrix_homeserver_app_service_
 #
 ######################################################################
 
+# Not enabled by default, for now
 matrix_synapse_auto_compressor_enabled: false
 
-matrix_synapse_auto_compressor_container_image_self_build: "{{ matrix_architecture not in ['arm32', 'arm64', 'amd64'] }}"
+matrix_synapse_auto_compressor_container_image_self_build: "{{ matrix_architecture not in ['amd64'] }}"
+
+matrix_synapse_auto_compressor_database_username: "{{ matrix_synapse_database_user if matrix_synapse_enabled else '' }}"
+matrix_synapse_auto_compressor_database_password: "{{ matrix_synapse_database_password if matrix_synapse_enabled else '' }}"
+matrix_synapse_auto_compressor_database_hostname: "{{ matrix_synapse_database_host if matrix_synapse_enabled else '' }}"
+matrix_synapse_auto_compressor_database_port: "{{ matrix_synapse_database_port if matrix_synapse_enabled else '5432' }}"
+matrix_synapse_auto_compressor_database_name: "{{ matrix_synapse_database_database if matrix_synapse_enabled else '' }}"
+
+matrix_synapse_auto_compressor_systemd_required_services_list: |
+  {{
+    ['docker.service']
+    +
+    ([devture_postgres_identifier ~ '.service'] if devture_postgres_enabled else [])
+  }}
 
 ######################################################################
 #

From 0f2e568b3098e63ca08af94416d0da37ce4a56ac Mon Sep 17 00:00:00 2001
From: Slavi Pantaleev <slavi@devture.com>
Date: Sun, 12 Mar 2023 09:56:53 +0200
Subject: [PATCH 05/10] Add validation tasks to matrix-synapse-auto-compressor

---
 .../matrix-synapse-auto-compressor/defaults/main.yml   |  2 +-
 .../matrix-synapse-auto-compressor/tasks/main.yml      |  3 +++
 .../tasks/validate_config.yml                          | 10 ++++++++++
 3 files changed, 14 insertions(+), 1 deletion(-)
 create mode 100644 roles/custom/matrix-synapse-auto-compressor/tasks/validate_config.yml

diff --git a/roles/custom/matrix-synapse-auto-compressor/defaults/main.yml b/roles/custom/matrix-synapse-auto-compressor/defaults/main.yml
index 99fb272f..8de4097e 100644
--- a/roles/custom/matrix-synapse-auto-compressor/defaults/main.yml
+++ b/roles/custom/matrix-synapse-auto-compressor/defaults/main.yml
@@ -27,7 +27,7 @@ matrix_synapse_auto_compressor_systemd_required_services_list: ['docker.service'
 matrix_synapse_auto_compressor_systemd_wanted_services_list: []
 
 matrix_synapse_auto_compressor_database_username: 'synapse'
-matrix_synapse_auto_compressor_database_password: 'some-password'
+matrix_synapse_auto_compressor_database_password: ''
 matrix_synapse_auto_compressor_database_hostname: ''
 matrix_synapse_auto_compressor_database_port: 5432
 matrix_synapse_auto_compressor_database_name: 'synapse'
diff --git a/roles/custom/matrix-synapse-auto-compressor/tasks/main.yml b/roles/custom/matrix-synapse-auto-compressor/tasks/main.yml
index b3549bd6..2cce1f12 100644
--- a/roles/custom/matrix-synapse-auto-compressor/tasks/main.yml
+++ b/roles/custom/matrix-synapse-auto-compressor/tasks/main.yml
@@ -1,6 +1,9 @@
 ---
 
 - block:
+    - when: matrix_synapse_auto_compressor_enabled | bool
+      ansible.builtin.include_tasks: "{{ role_path }}/tasks/validate_config.yml"
+
     - when: matrix_synapse_auto_compressor_enabled | bool
       ansible.builtin.include_tasks: "{{ role_path }}/tasks/install.yml"
   tags:
diff --git a/roles/custom/matrix-synapse-auto-compressor/tasks/validate_config.yml b/roles/custom/matrix-synapse-auto-compressor/tasks/validate_config.yml
new file mode 100644
index 00000000..b0dbfab0
--- /dev/null
+++ b/roles/custom/matrix-synapse-auto-compressor/tasks/validate_config.yml
@@ -0,0 +1,10 @@
+---
+
+- name: Fail if required matrix-synapse-auto-compressor settings not defined
+  ansible.builtin.fail:
+    msg: >
+      You need to define a required configuration setting (`{{ item }}`).
+  when: "vars[item] == ''"
+  with_items:
+    - matrix_synapse_auto_compressor_database_hostname
+    - matrix_synapse_auto_compressor_database_password

From 26d5719df414d26f3af8470cac5a36d1f3e65eed Mon Sep 17 00:00:00 2001
From: Slavi Pantaleev <slavi@devture.com>
Date: Sun, 12 Mar 2023 10:01:51 +0200
Subject: [PATCH 06/10] Make matrix-synapse-auto-compressor live in its own
 container network

It will, additionally, be connected to the devture-postgres network, if
devture-postgres is enabled.
---
 group_vars/matrix_servers                           |  5 +++++
 .../defaults/main.yml                               |  8 ++++++++
 .../tasks/install.yml                               |  5 +++++
 .../matrix-synapse-auto-compressor.service.j2       | 13 +++++++++++--
 4 files changed, 29 insertions(+), 2 deletions(-)

diff --git a/group_vars/matrix_servers b/group_vars/matrix_servers
index 5712b037..c96b34a7 100755
--- a/group_vars/matrix_servers
+++ b/group_vars/matrix_servers
@@ -3338,6 +3338,11 @@ matrix_synapse_auto_compressor_enabled: false
 
 matrix_synapse_auto_compressor_container_image_self_build: "{{ matrix_architecture not in ['amd64'] }}"
 
+matrix_synapse_auto_compressor_container_additional_networks: |
+  {{
+    ([devture_postgres_container_network] if devture_postgres_enabled and devture_postgres_container_network != matrix_synapse_auto_compressor_container_network else [])
+  }}
+
 matrix_synapse_auto_compressor_database_username: "{{ matrix_synapse_database_user if matrix_synapse_enabled else '' }}"
 matrix_synapse_auto_compressor_database_password: "{{ matrix_synapse_database_password if matrix_synapse_enabled else '' }}"
 matrix_synapse_auto_compressor_database_hostname: "{{ matrix_synapse_database_host if matrix_synapse_enabled else '' }}"
diff --git a/roles/custom/matrix-synapse-auto-compressor/defaults/main.yml b/roles/custom/matrix-synapse-auto-compressor/defaults/main.yml
index 8de4097e..0649392d 100644
--- a/roles/custom/matrix-synapse-auto-compressor/defaults/main.yml
+++ b/roles/custom/matrix-synapse-auto-compressor/defaults/main.yml
@@ -17,6 +17,14 @@ matrix_synapse_auto_compressor_container_image_force_pull: "{{ matrix_synapse_au
 
 matrix_synapse_auto_compressor_base_path: "{{ matrix_base_data_path }}/synapse-auto-compressor"
 
+# The base container network. It will be auto-created by this role if it doesn't exist already.
+matrix_synapse_auto_compressor_container_network: matrix-synapse-auto-compressor
+
+# A list of additional container networks that the container would be connected to.
+# The role does not create these networks, so make sure they already exist.
+# Use this to expose this container to another reverse proxy, which runs in a different container network.
+matrix_synapse_auto_compressor_container_additional_networks: []
+
 # A list of extra arguments to pass to the container
 matrix_synapse_auto_compressor_container_extra_arguments: []
 
diff --git a/roles/custom/matrix-synapse-auto-compressor/tasks/install.yml b/roles/custom/matrix-synapse-auto-compressor/tasks/install.yml
index ec825b13..6f4524bb 100644
--- a/roles/custom/matrix-synapse-auto-compressor/tasks/install.yml
+++ b/roles/custom/matrix-synapse-auto-compressor/tasks/install.yml
@@ -43,6 +43,11 @@
       pull: true
   when: "matrix_synapse_auto_compressor_container_image_self_build | bool"
 
+- name: Ensure matrix-synapse-auto-compressor container network is created
+  community.general.docker_network:
+    name: "{{ matrix_synapse_auto_compressor_container_network }}"
+    driver: bridge
+
 - name: Ensure matrix-synapse-auto-compressor systemd service and timer are installed
   ansible.builtin.template:
     src: "{{ role_path }}/templates/matrix-synapse-auto-compressor.{{ item }}.j2"
diff --git a/roles/custom/matrix-synapse-auto-compressor/templates/matrix-synapse-auto-compressor.service.j2 b/roles/custom/matrix-synapse-auto-compressor/templates/matrix-synapse-auto-compressor.service.j2
index 02aef84b..e769438d 100644
--- a/roles/custom/matrix-synapse-auto-compressor/templates/matrix-synapse-auto-compressor.service.j2
+++ b/roles/custom/matrix-synapse-auto-compressor/templates/matrix-synapse-auto-compressor.service.j2
@@ -15,18 +15,27 @@ Type=oneshot
 Environment="HOME={{ devture_systemd_docker_base_systemd_unit_home_path }}"
 ExecStartPre=-{{ devture_systemd_docker_base_host_command_sh }} -c '{{ devture_systemd_docker_base_host_command_docker }} kill matrix-synapse-auto-compressor 2>/dev/null || true'
 ExecStartPre=-{{ devture_systemd_docker_base_host_command_sh }} -c '{{ devture_systemd_docker_base_host_command_docker }} rm matrix-synapse-auto-compressor 2>/dev/null || true'
-ExecStart={{ devture_systemd_docker_base_host_command_docker }} run --rm --name matrix-synapse-auto-compressor \
+
+ExecStartPre={{ devture_systemd_docker_base_host_command_docker }} create \
+			--rm \
+			--name=matrix-synapse-auto-compressor \
 			--log-driver=none \
 			--cap-drop=ALL \
 			--read-only \
 			--user={{ matrix_user_uid }}:{{ matrix_user_gid }} \
-			--network={{ matrix_docker_network }} \
+			--network={{ matrix_synapse_auto_compressor_container_network }} \
 			{% for arg in matrix_synapse_auto_compressor_container_extra_arguments %}
 			{{ arg }} \
 			{% endfor %}
 			{{ matrix_synapse_auto_compressor_container_image }} \
 			{{ matrix_synapse_auto_compressor_command }}
 
+{% for network in matrix_synapse_auto_compressor_container_additional_networks %}
+ExecStartPre={{ devture_systemd_docker_base_host_command_docker }} network connect {{ network }} matrix-synapse-auto-compressor
+{% endfor %}
+
+ExecStart={{ devture_systemd_docker_base_host_command_docker }} start --attach matrix-synapse-auto-compressor
+
 ExecStop=-{{ devture_systemd_docker_base_host_command_sh }} -c '{{ devture_systemd_docker_base_host_command_docker }} kill matrix-synapse-auto-compressor 2>/dev/null || true'
 ExecStop=-{{ devture_systemd_docker_base_host_command_sh }} -c '{{ devture_systemd_docker_base_host_command_docker }} rm matrix-synapse-auto-compressor 2>/dev/null || true'
 SyslogIdentifier=matrix-synapse-auto-compressor

From 328d0d8a5f47c4f4e15d70cb4c796dbd6a957b6b Mon Sep 17 00:00:00 2001
From: Slavi Pantaleev <slavi@devture.com>
Date: Sun, 12 Mar 2023 10:17:42 +0200
Subject: [PATCH 07/10] Move synapse-auto-compressor Postgres argument to an
 environment variable

This provides an additional security benefit. The password won't leak in
the process list anymore.
---
 .../defaults/main.yml                          | 14 +++++++++-----
 .../tasks/install.yml                          | 18 ++++++++++++++++--
 .../templates/env.j2                           |  1 +
 .../matrix-synapse-auto-compressor.service.j2  |  4 +++-
 4 files changed, 29 insertions(+), 8 deletions(-)
 create mode 100644 roles/custom/matrix-synapse-auto-compressor/templates/env.j2

diff --git a/roles/custom/matrix-synapse-auto-compressor/defaults/main.yml b/roles/custom/matrix-synapse-auto-compressor/defaults/main.yml
index 0649392d..61194714 100644
--- a/roles/custom/matrix-synapse-auto-compressor/defaults/main.yml
+++ b/roles/custom/matrix-synapse-auto-compressor/defaults/main.yml
@@ -5,18 +5,19 @@
 
 matrix_synapse_auto_compressor_enabled: true
 
+matrix_synapse_auto_compressor_version: v0.1.3
+
+matrix_synapse_auto_compressor_base_path: "{{ matrix_base_data_path }}/synapse-auto-compressor"
+matrix_synapse_auto_compressor_container_src_files_path: "{{ matrix_synapse_auto_compressor_base_path }}/container-src"
+
 matrix_synapse_auto_compressor_container_image_self_build: false
 matrix_synapse_auto_compressor_container_repo: "https://gitlab.com/etke.cc/rust-synapse-compress-state.git"
 matrix_synapse_auto_compressor_container_repo_version: "{{ 'main' if matrix_synapse_auto_compressor_version == 'latest' else matrix_synapse_auto_compressor_version }}"
-matrix_synapse_auto_compressor_container_src_files_path: "{{ matrix_synapse_auto_compressor_base_path }}"
 
-matrix_synapse_auto_compressor_version: v0.1.3
 matrix_synapse_auto_compressor_container_image: "{{ matrix_synapse_auto_compressor_container_image_name_prefix }}etke.cc/rust-synapse-compress-state:{{ matrix_synapse_auto_compressor_version }}"
 matrix_synapse_auto_compressor_container_image_name_prefix: "{{ 'localhost/' if matrix_synapse_auto_compressor_container_image_self_build else 'registry.gitlab.com/' }}"
 matrix_synapse_auto_compressor_container_image_force_pull: "{{ matrix_synapse_auto_compressor_container_image.endswith(':latest') }}"
 
-matrix_synapse_auto_compressor_base_path: "{{ matrix_base_data_path }}/synapse-auto-compressor"
-
 # The base container network. It will be auto-created by this role if it doesn't exist already.
 matrix_synapse_auto_compressor_container_network: matrix-synapse-auto-compressor
 
@@ -57,4 +58,7 @@ matrix_synapse_auto_compressor_chunk_size: 500
 # The higher this number is set to, the longer the compressor will run for.
 matrix_synapse_auto_compressor_chunks_to_compress: 100
 
-matrix_synapse_auto_compressor_command: "synapse_auto_compressor -p {{ matrix_synapse_auto_compressor_synapse_database }} -c {{ matrix_synapse_auto_compressor_chunk_size }} -n {{ matrix_synapse_auto_compressor_chunks_to_compress }}"
+matrix_synapse_auto_compressor_command: "synapse_auto_compressor -p $POSTGRES_LOCATION -c {{ matrix_synapse_auto_compressor_chunk_size }} -n {{ matrix_synapse_auto_compressor_chunks_to_compress }}"
+
+# Controls the POSTGRES_LOCATION environment variable
+matrix_synapse_auto_compressor_environment_variable_postgres_location: "{{ matrix_synapse_auto_compressor_synapse_database }}"
diff --git a/roles/custom/matrix-synapse-auto-compressor/tasks/install.yml b/roles/custom/matrix-synapse-auto-compressor/tasks/install.yml
index 6f4524bb..494a5678 100644
--- a/roles/custom/matrix-synapse-auto-compressor/tasks/install.yml
+++ b/roles/custom/matrix-synapse-auto-compressor/tasks/install.yml
@@ -1,12 +1,26 @@
 ---
+
 - name: Ensure synapse-auto-compressor paths exist
   ansible.builtin.file:
-    path: "{{ matrix_synapse_auto_compressor_container_src_files_path }}"
+    path: "{{ item.path }}"
     state: directory
     mode: 0750
     owner: "{{ matrix_user_username }}"
     group: "{{ matrix_user_groupname }}"
-  when: matrix_synapse_auto_compressor_container_image_self_build | bool
+  when: item.when | bool
+  with_items:
+    - path: "{{ matrix_synapse_auto_compressor_base_path }}"
+      when: true
+    - path: "{{ matrix_synapse_auto_compressor_container_src_files_path }}"
+      when: "{{ matrix_synapse_auto_compressor_container_image_self_build }}"
+
+- name: Ensure synapse-auto-compressor labels installed
+  ansible.builtin.template:
+    src: "{{ role_path }}/templates/env.j2"
+    dest: "{{ matrix_synapse_auto_compressor_base_path }}/env"
+    mode: 0640
+    owner: "{{ matrix_user_username }}"
+    group: "{{ matrix_user_groupname }}"
 
 - name: Ensure synapse-auto-compressor image is pulled
   community.docker.docker_image:
diff --git a/roles/custom/matrix-synapse-auto-compressor/templates/env.j2 b/roles/custom/matrix-synapse-auto-compressor/templates/env.j2
new file mode 100644
index 00000000..27fb1dd8
--- /dev/null
+++ b/roles/custom/matrix-synapse-auto-compressor/templates/env.j2
@@ -0,0 +1 @@
+POSTGRES_LOCATION={{ matrix_synapse_auto_compressor_environment_variable_postgres_location }}
diff --git a/roles/custom/matrix-synapse-auto-compressor/templates/matrix-synapse-auto-compressor.service.j2 b/roles/custom/matrix-synapse-auto-compressor/templates/matrix-synapse-auto-compressor.service.j2
index e769438d..f530d5b2 100644
--- a/roles/custom/matrix-synapse-auto-compressor/templates/matrix-synapse-auto-compressor.service.j2
+++ b/roles/custom/matrix-synapse-auto-compressor/templates/matrix-synapse-auto-compressor.service.j2
@@ -24,11 +24,13 @@ ExecStartPre={{ devture_systemd_docker_base_host_command_docker }} create \
 			--read-only \
 			--user={{ matrix_user_uid }}:{{ matrix_user_gid }} \
 			--network={{ matrix_synapse_auto_compressor_container_network }} \
+			--env-file={{ matrix_synapse_auto_compressor_base_path }}/env \
+			--entrypoint=/bin/sh \
 			{% for arg in matrix_synapse_auto_compressor_container_extra_arguments %}
 			{{ arg }} \
 			{% endfor %}
 			{{ matrix_synapse_auto_compressor_container_image }} \
-			{{ matrix_synapse_auto_compressor_command }}
+			-c '{{ matrix_synapse_auto_compressor_command }}'
 
 {% for network in matrix_synapse_auto_compressor_container_additional_networks %}
 ExecStartPre={{ devture_systemd_docker_base_host_command_docker }} network connect {{ network }} matrix-synapse-auto-compressor

From 7422337c26c464242b0295aad2c64c1735f65bf1 Mon Sep 17 00:00:00 2001
From: Slavi Pantaleev <slavi@devture.com>
Date: Sun, 12 Mar 2023 10:18:16 +0200
Subject: [PATCH 08/10] Add missing matrix-synapse-auto-compressor.timer in
 systemd service list

---
 group_vars/matrix_servers | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/group_vars/matrix_servers b/group_vars/matrix_servers
index c96b34a7..60c8349e 100755
--- a/group_vars/matrix_servers
+++ b/group_vars/matrix_servers
@@ -338,6 +338,8 @@ devture_systemd_service_manager_services_list_auto: |
     +
     ([{'name': 'matrix-synapse-s3-storage-provider-migrate.timer', 'priority': 5000, 'groups': ['matrix']}] if matrix_synapse_ext_synapse_s3_storage_provider_enabled else [])
     +
+    ([{'name': 'matrix-synapse-auto-compressor.timer', 'priority': 5000, 'groups': ['matrix', 'synapse-auto-compressor']}] if matrix_synapse_auto_compressor_enabled else [])
+    +
     ([{'name': 'matrix-synapse-admin.service', 'priority': 4000, 'groups': ['matrix', 'synapse-admin']}] if matrix_synapse_admin_enabled else [])
     +
     ([{'name': 'matrix-synapse-reverse-proxy-companion.service', 'priority': 1500, 'groups': ['matrix', 'homeservers', 'synapse', 'reverse-proxies']}] if matrix_synapse_reverse_proxy_companion_enabled else [])

From bb89d7b3fb063339c40dad937cf5a275603e868d Mon Sep 17 00:00:00 2001
From: Slavi Pantaleev <slavi@devture.com>
Date: Sun, 12 Mar 2023 10:39:19 +0200
Subject: [PATCH 09/10] Fix self-building for matrix-synapse-auto-compressor

---
 roles/custom/matrix-synapse-auto-compressor/defaults/main.yml | 4 ++--
 roles/custom/matrix-synapse-auto-compressor/tasks/install.yml | 4 ++--
 2 files changed, 4 insertions(+), 4 deletions(-)

diff --git a/roles/custom/matrix-synapse-auto-compressor/defaults/main.yml b/roles/custom/matrix-synapse-auto-compressor/defaults/main.yml
index 61194714..48ed1b03 100644
--- a/roles/custom/matrix-synapse-auto-compressor/defaults/main.yml
+++ b/roles/custom/matrix-synapse-auto-compressor/defaults/main.yml
@@ -11,8 +11,8 @@ matrix_synapse_auto_compressor_base_path: "{{ matrix_base_data_path }}/synapse-a
 matrix_synapse_auto_compressor_container_src_files_path: "{{ matrix_synapse_auto_compressor_base_path }}/container-src"
 
 matrix_synapse_auto_compressor_container_image_self_build: false
-matrix_synapse_auto_compressor_container_repo: "https://gitlab.com/etke.cc/rust-synapse-compress-state.git"
-matrix_synapse_auto_compressor_container_repo_version: "{{ 'main' if matrix_synapse_auto_compressor_version == 'latest' else matrix_synapse_auto_compressor_version }}"
+matrix_synapse_auto_compressor_container_image_self_build_repo: "https://github.com/matrix-org/rust-synapse-compress-state.git"
+matrix_synapse_auto_compressor_container_image_self_build_version: "{{ 'main' if matrix_synapse_auto_compressor_version == 'latest' else matrix_synapse_auto_compressor_version }}"
 
 matrix_synapse_auto_compressor_container_image: "{{ matrix_synapse_auto_compressor_container_image_name_prefix }}etke.cc/rust-synapse-compress-state:{{ matrix_synapse_auto_compressor_version }}"
 matrix_synapse_auto_compressor_container_image_name_prefix: "{{ 'localhost/' if matrix_synapse_auto_compressor_container_image_self_build else 'registry.gitlab.com/' }}"
diff --git a/roles/custom/matrix-synapse-auto-compressor/tasks/install.yml b/roles/custom/matrix-synapse-auto-compressor/tasks/install.yml
index 494a5678..be4d5aad 100644
--- a/roles/custom/matrix-synapse-auto-compressor/tasks/install.yml
+++ b/roles/custom/matrix-synapse-auto-compressor/tasks/install.yml
@@ -36,8 +36,8 @@
 
 - name: Ensure synapse-auto-compressor repository is present on self-build
   ansible.builtin.git:
-    repo: "{{ matrix_synapse_auto_compressor_container_repo }}"
-    version: "{{ matrix_synapse_auto_compressor_container_repo_version }}"
+    repo: "{{ matrix_synapse_auto_compressor_container_image_self_build_repo }}"
+    version: "{{ matrix_synapse_auto_compressor_container_image_self_build_version }}"
     dest: "{{ matrix_synapse_auto_compressor_container_src_files_path }}"
     force: "yes"
   become: true

From d3a0ef22b61b97d9242efc9a2021296983fd47a6 Mon Sep 17 00:00:00 2001
From: Slavi Pantaleev <slavi@devture.com>
Date: Sun, 12 Mar 2023 10:55:08 +0200
Subject: [PATCH 10/10] Announce matrix-synapse-auto-compressor

---
 CHANGELOG.md                 | 16 ++++++++++++++++
 docs/configuring-playbook.md |  2 ++
 docs/maintenance-synapse.md  |  4 +++-
 3 files changed, 21 insertions(+), 1 deletion(-)

diff --git a/CHANGELOG.md b/CHANGELOG.md
index 7e9e2545..9ba17ea3 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,3 +1,19 @@
+# 2023-03-12
+
+## synapse-auto-compressor support
+
+Thanks to [Aine](https://gitlab.com/etke.cc) of [etke.cc](https://etke.cc/), the playbook can now set up [rust-synapse-compress-state](https://github.com/matrix-org/rust-synapse-compress-state)'s `synapse_auto_compressor` tool to run periodically.
+
+If enabled, `synapse_auto_compressor` runs on a schedule and compresses your Synapse database's `state_groups` table. It was possible to run `rust-synapse-compress-state` manually via the playbook even before - see [Compressing state with rust-synapse-compress-state](docs/maintenance-synapse.md#compressing-state-with-rust-synapse-compress-state). However, using `synapse_auto_compressor` is better, because:
+
+- it runs on a more up-to-date version of `rust-synapse-compress-state`
+- it's a set-it-and-forget-it tool that you can enable and never have to deal with manual compression anymore
+
+This tool needs to be enabled manually, for now. In the future, we're considering enabling it by default for all Synapse installations.
+
+See our [Setting up synapse-auto-compressor](docs/configuring-playbook-synapse-auto-compressor.md) documentation to get started.
+
+
 # 2023-03-07
 
 ## Sliding Sync Proxy (Element X) support
diff --git a/docs/configuring-playbook.md b/docs/configuring-playbook.md
index 68a2658a..a65858f0 100644
--- a/docs/configuring-playbook.md
+++ b/docs/configuring-playbook.md
@@ -195,6 +195,8 @@ When you're done with all the configuration you'd like to do, continue with [Ins
 
 ### Other specialized services
 
+- [Setting up synapse-auto-compressor](configuring-playbook-synapse-auto-compressor.md) for compressing the database on Synapse homeservers (optional)
+
 - [Setting up the Sliding Sync Proxy](configuring-playbook-sliding-sync-proxy.md) for clients which require Sliding Sync support (like Element X) (optional)
 
 - [Setting up the Sygnal push gateway](configuring-playbook-sygnal.md) (optional)
diff --git a/docs/maintenance-synapse.md b/docs/maintenance-synapse.md
index a51811ff..7c3ecc1b 100644
--- a/docs/maintenance-synapse.md
+++ b/docs/maintenance-synapse.md
@@ -29,7 +29,9 @@ After deleting data, you may wish to run a [`FULL` Postgres `VACUUM`](./maintena
 
 [rust-synapse-compress-state](https://github.com/matrix-org/rust-synapse-compress-state) can be used to optimize some `_state` tables used by Synapse. If your server participates in large rooms this is the most effective way to reduce the size of your database.
 
-This tool should be safe to use (even when Synapse is running), but it's always a good idea to [make Postgres backups](./maintenance-postgres.md#backing-up-postgresql) first.
+**Note**: besides running the `rust-synapse-compress-state` tool manually, you can also enable its `synapse-auto-compressor` tool by [Setting up synapse-auto-compressor](configuring-playbook-synapse-auto-compressor.md). The automatic tool will run on a schedule every day and you won't have to compress state manually ever again.
+
+`rust-synapse-compress-state` should be safe to use (even when Synapse is running), but it's always a good idea to [make Postgres backups](./maintenance-postgres.md#backing-up-postgresql) first.
 
 To ask the playbook to run rust-synapse-compress-state, execute: