Add support for istio LEAST_REQUEST destination rule load balancing a…

…lgorithm Signed-off-by: Ivan Lopes <[email protected]>
fluxcd · May 25, 2023 · 18e6afa · 18e6afa
1 parent e71ce18
commit 18e6afa
Show file tree

Hide file tree

Showing 4 changed files with 9 additions and 0 deletions.
diff --git a/artifacts/flagger/crd.yaml b/artifacts/flagger/crd.yaml
@@ -751,6 +751,7 @@ spec:
                                 - LEAST_CONN
                                 - RANDOM
                                 - PASSTHROUGH
+                                - LEAST_REQUEST
                               type: string
                         outlierDetection:
                           description: Settings controlling eviction of unhealthy hosts from the load balancing pool.

diff --git a/charts/flagger/crds/crd.yaml b/charts/flagger/crds/crd.yaml
@@ -751,6 +751,7 @@ spec:
                                 - LEAST_CONN
                                 - RANDOM
                                 - PASSTHROUGH
+                                - LEAST_REQUEST
                               type: string
                         outlierDetection:
                           description: Settings controlling eviction of unhealthy hosts from the load balancing pool.

diff --git a/kustomize/base/flagger/crd.yaml b/kustomize/base/flagger/crd.yaml
@@ -751,6 +751,7 @@ spec:
                                 - LEAST_CONN
                                 - RANDOM
                                 - PASSTHROUGH
+                                - LEAST_REQUEST
                               type: string
                         outlierDetection:
                           description: Settings controlling eviction of unhealthy hosts from the load balancing pool.

diff --git a/pkg/apis/istio/v1alpha3/destination_rule.go b/pkg/apis/istio/v1alpha3/destination_rule.go
@@ -419,6 +419,12 @@ const (
 	// advanced use cases. Refer to Original Destination load balancer in
 	// Envoy for further details.
 	SimpleLBPassthrough SimpleLB = "PASSTHROUGH"
+
+	// The least request load balancer spreads load across endpoints,
+	// favoring endpoints with the least outstanding requests. This is generally
+	// safer and outperforms ROUND_ROBIN in nearly all cases. Prefer to use LEAST_REQUEST
+	// as a drop-in replacement for ROUND_ROBIN.
+	SimpleLBLeastRequest SimpleLB = "LEAST_REQUEST"
 )
 
 // Consistent Hash-based load balancing can be used to provide soft