Add feature flag for merge throttling policy

Two options; `STATIC` (default) and `DYNAMIC`. Does not currently set
any window size configs based on the existing feature flag for max
pending, so the config defaults will be used for these when dynamic
throttling is enabled.

1 files changed, 19 insertions, 0 deletions

diff --git a/config-model/src/test/java/com/yahoo/vespa/model/content/StorageClusterTest.java b/config-model/src/test/java/com/yahoo/vespa/model/content/StorageClusterTest.java
index 06b907ca2c2..2953b0cb32d 100644
--- a/config-model/src/test/java/com/yahoo/vespa/model/content/StorageClusterTest.java
+++ b/config-model/src/test/java/com/yahoo/vespa/model/content/StorageClusterTest.java
@@ -160,6 +160,25 @@ public class StorageClusterTest {
     }
 
     @Test
+    public void merge_throttling_policy_config_defaults_to_static() {
+        var config = configFromProperties(new TestProperties());
+        assertEquals(StorServerConfig.Merge_throttling_policy.Type.STATIC, config.merge_throttling_policy().type());
+    }
+
+    @Test
+    public void merge_throttling_policy_config_is_derived_from_flag() {
+        var config = configFromProperties(new TestProperties().setMergeThrottlingPolicy("STATIC"));
+        assertEquals(StorServerConfig.Merge_throttling_policy.Type.STATIC, config.merge_throttling_policy().type());
+
+        config = configFromProperties(new TestProperties().setMergeThrottlingPolicy("DYNAMIC"));
+        assertEquals(StorServerConfig.Merge_throttling_policy.Type.DYNAMIC, config.merge_throttling_policy().type());
+
+        // Invalid enum values fall back to the default
+        config = configFromProperties(new TestProperties().setMergeThrottlingPolicy("UKULELE"));
+        assertEquals(StorServerConfig.Merge_throttling_policy.Type.STATIC, config.merge_throttling_policy().type());
+    }
+
+    @Test
     public void testVisitors() {
         StorVisitorConfig.Builder builder = new StorVisitorConfig.Builder();
         parse(cluster("bees",