Use bucket_space metric in retirement

This makes the Cluster Controller use the
vds.datastored.bucket_space.buckets_total, dimension bucketSpace=default, to
determine whether a content node manages zero buckets, and if so, will allow
the node to go permanently down. This is used when a node is retiring, and it
is to be removed from the application.

The change is guarded by the use-bucket-space-metric, default true. If the new
metric doesn't work as expected, we can revert to using the current/old metric
by flipping the flag. The flag can be controlled per application.

1 files changed, 6 insertions, 0 deletions

diff --git a/configserver/src/main/java/com/yahoo/vespa/config/server/deploy/ModelContextImpl.java b/configserver/src/main/java/com/yahoo/vespa/config/server/deploy/ModelContextImpl.java
index 694ab8f037e..52d47a9398b 100644
--- a/configserver/src/main/java/com/yahoo/vespa/config/server/deploy/ModelContextImpl.java
+++ b/configserver/src/main/java/com/yahoo/vespa/config/server/deploy/ModelContextImpl.java
@@ -132,6 +132,7 @@ public class ModelContextImpl implements ModelContext {
         private final boolean useAdaptiveDispatch;
         private final Optional<TlsSecrets> tlsSecrets;
         private final double defaultTermwiseLimit;
+        private final boolean useBucketSpaceMetric;
 
         public Properties(ApplicationId applicationId,
                           boolean multitenantFromConfig,
@@ -162,6 +163,8 @@ public class ModelContextImpl implements ModelContext {
             this.tlsSecrets = tlsSecrets;
             defaultTermwiseLimit = Flags.DEFAULT_TERM_WISE_LIMIT.bindTo(flagSource)
                     .with(FetchVector.Dimension.APPLICATION_ID, applicationId.serializedForm()).value();
+            this.useBucketSpaceMetric = Flags.USE_BUCKET_SPACE_METRIC.bindTo(flagSource)
+                    .with(FetchVector.Dimension.APPLICATION_ID, applicationId.serializedForm()).value();
         }
 
         @Override
@@ -209,6 +212,9 @@ public class ModelContextImpl implements ModelContext {
 
         @Override
         public double defaultTermwiseLimit() { return defaultTermwiseLimit; }
+
+        @Override
+        public boolean useBucketSpaceMetric() { return useBucketSpaceMetric; }
     }
 
 }