From edce2b528d66375b2f4bb50c25221153947bcb28 Mon Sep 17 00:00:00 2001
From: peterw <12556909+pedro-peter@users.noreply.github.com>
Date: Mon, 24 Jun 2024 04:14:56 +0100
Subject: [PATCH] add cilium_hubble_event_buffer_capacity &
 cilium_hubble_event_queue_size vars (#10943)

---
 inventory/sample/group_vars/k8s_cluster/k8s-net-cilium.yml | 7 +++++++
 roles/network_plugin/cilium/defaults/main.yml              | 6 ++++++
 roles/network_plugin/cilium/tasks/check.yml                | 6 ++++++
 roles/network_plugin/cilium/templates/cilium/config.yml.j2 | 6 ++++++
 4 files changed, 25 insertions(+)

diff --git a/inventory/sample/group_vars/k8s_cluster/k8s-net-cilium.yml b/inventory/sample/group_vars/k8s_cluster/k8s-net-cilium.yml
index db827437e..a583540ba 100644
--- a/inventory/sample/group_vars/k8s_cluster/k8s-net-cilium.yml
+++ b/inventory/sample/group_vars/k8s_cluster/k8s-net-cilium.yml
@@ -163,6 +163,13 @@ cilium_l2announcements: false
 ### Enable auto generate certs if cilium_hubble_install: true
 # cilium_hubble_tls_generate: false
 
+### Tune cilium_hubble_event_buffer_capacity & cilium_hubble_event_queue_size values to avoid dropping events when hubble is under heavy load
+### Capacity of Hubble events buffer. The provided value must be one less than an integer power of two and no larger than 65535
+### (ie: 1, 3, ..., 2047, 4095, ..., 65535) (default 4095)
+# cilium_hubble_event_buffer_capacity: 4095
+### Buffer size of the channel to receive monitor events.
+# cilium_hubble_event_queue_size: 50
+
 # IP address management mode for v1.9+.
 # https://docs.cilium.io/en/v1.9/concepts/networking/ipam/
 # cilium_ipam_mode: kubernetes
diff --git a/roles/network_plugin/cilium/defaults/main.yml b/roles/network_plugin/cilium/defaults/main.yml
index 2f4830a8e..7e65e7faf 100644
--- a/roles/network_plugin/cilium/defaults/main.yml
+++ b/roles/network_plugin/cilium/defaults/main.yml
@@ -159,6 +159,12 @@ cilium_hubble_install: false
 ### Enable auto generate certs if cilium_hubble_install: true
 cilium_hubble_tls_generate: false
 
+### Capacity of Hubble events buffer. The provided value must be one less than an integer power of two and no larger than 65535
+### (ie: 1, 3, ..., 2047, 4095, ..., 65535) (default 4095)
+# cilium_hubble_event_buffer_capacity: 4095
+### Buffer size of the channel to receive monitor events.
+# cilium_hubble_event_queue_size: 50
+
 # The default IP address management mode is "Cluster Scope".
 # https://docs.cilium.io/en/stable/concepts/networking/ipam/
 cilium_ipam_mode: cluster-pool
diff --git a/roles/network_plugin/cilium/tasks/check.yml b/roles/network_plugin/cilium/tasks/check.yml
index c65591f66..34a5afebb 100644
--- a/roles/network_plugin/cilium/tasks/check.yml
+++ b/roles/network_plugin/cilium/tasks/check.yml
@@ -61,3 +61,9 @@
   when:
     - cilium_ipsec_enabled is defined
     - cilium_ipsec_enabled
+
+- name: Stop if cilium_hubble_event_buffer_capacity is not a power of 2 minus 1 and is not between 1 and 65535
+  assert:
+    that: "cilium_hubble_event_buffer_capacity in [1, 3, 7, 15, 31, 63, 127, 255, 511, 1023, 2047, 4095, 8191, 16383, 32767, 65535]"
+    msg: "Error: cilium_hubble_event_buffer_capacity:{{ cilium_hubble_event_buffer_capacity }} is not a power of 2 minus 1 and it should be between 1 and 65535."
+  when: cilium_hubble_event_buffer_capacity is defined
diff --git a/roles/network_plugin/cilium/templates/cilium/config.yml.j2 b/roles/network_plugin/cilium/templates/cilium/config.yml.j2
index bdb07212b..ed37f122f 100644
--- a/roles/network_plugin/cilium/templates/cilium/config.yml.j2
+++ b/roles/network_plugin/cilium/templates/cilium/config.yml.j2
@@ -192,6 +192,12 @@ data:
 {% for hubble_metrics_cycle in cilium_hubble_metrics %}
     {{ hubble_metrics_cycle }}
 {% endfor %}
+{% endif %}
+{% if cilium_hubble_event_buffer_capacity is defined %}
+  hubble-event-buffer-capacity: "{{ cilium_hubble_event_buffer_capacity }}"
+{% endif %}
+{% if cilium_hubble_event_queue_size is defined %}
+  hubble-event-queue-size: "{{ cilium_hubble_event_queue_size }}"
 {% endif %}
   hubble-listen-address: ":4244"
 {% if cilium_enable_hubble and cilium_hubble_install %}