From c55fd94b67c2eeeff5648ab332186bb71e1b246c Mon Sep 17 00:00:00 2001
From: Robert Kwolek <robert.kwolek@gmail.com>
Date: Thu, 20 Aug 2020 21:38:11 +0200
Subject: [PATCH] doc: weighted rollout doc added

---
 .../tutorials/linkerd-progressive-delivery.md | 40 +++++++++++++++++++
 1 file changed, 40 insertions(+)

diff --git a/docs/gitbook/tutorials/linkerd-progressive-delivery.md b/docs/gitbook/tutorials/linkerd-progressive-delivery.md
index 87c161d1..216235bf 100644
--- a/docs/gitbook/tutorials/linkerd-progressive-delivery.md
+++ b/docs/gitbook/tutorials/linkerd-progressive-delivery.md
@@ -109,6 +109,46 @@ spec:
           cmd: "hey -z 2m -q 10 -c 2 http://podinfo-canary.test:9898/"
 ```
 
+### Rollout Weights
+
+By default Flagger allows to use linear promotion metrics, with the start value, the step and maximum weight value in 0 to 100 range.  
+
+Example:
+```yaml
+canary:
+  analysis:
+    promotion:
+      maxWeight: 50
+      stepWeight: 20
+```
+This configuration performs analysis starting from 20, increasing by 20 until weight goes above 50.  
+We would have steps (canary weight : primary weight):
+* 20 (20 : 80)
+* 40 (40 : 60)
+* 60 (60 : 40)
+* promotion
+
+In order to enable non-linear promotion a new parameters were introduced:
+* `fullWeight` - determines the sum of canary and primary weights, i.e. the maximum possible weight which can be set to the split
+* `stepWeights` - determines the ordered array of weights, which shall be used during canary promotion.
+
+Example:
+```yaml
+canary:
+  analysis:
+    promotion:
+      fullWeight: 1000
+      maxWeight: 500
+      stepWeights: [1, 10, 100, 800]
+```
+This configuration performs analysis starting from 1, going through `stepWeights` values till 800.  
+We would have steps (canary weight : primary weight):
+* 1   (1 : 999)
+* 10  (10 : 990)
+* 100 (100 : 900)
+* 800 (800 : 200)
+* promotion
+
 Save the above resource as podinfo-canary.yaml and then apply it:
 
 ```bash