Allow preprovision capacity on partially filled hosts

Adds new functionality that can be disabled by setting the
compact-preprovision-capacity flag to false.

preprovision-capacity can be satisfied by hosts with spare resources.  The
DynamicProvisioningMaintainer does this as follows:
 1. For each cluster in preprovision-capacity, try to
    a. allocate the cluster using NodePrioritizer
    b. If there is a deficit, provision the deficit with HostProvisioner, which
       may provision larger shared hosts depending on shared-hosts, and retry
       (1) from the first cluster again.
    c. Otherwise, pretend the nodes are allocated and go to next cluster.
 2. All of preprovision-capacity was successfully allocated, and empty hosts
    are therefore excess that can be deprovisioned.

4 files changed, 142 insertions, 79 deletions

diff --git a/flags/src/main/java/com/yahoo/vespa/flags/Flags.java b/flags/src/main/java/com/yahoo/vespa/flags/Flags.java
index cd60a082472..bdbe439dcdf 100644
--- a/flags/src/main/java/com/yahoo/vespa/flags/Flags.java
+++ b/flags/src/main/java/com/yahoo/vespa/flags/Flags.java
@@ -3,7 +3,7 @@ package com.yahoo.vespa.flags;
 
 import com.yahoo.component.Vtag;
 import com.yahoo.vespa.defaults.Defaults;
-import com.yahoo.vespa.flags.custom.HostCapacity;
+import com.yahoo.vespa.flags.custom.ClusterCapacity;
 import com.yahoo.vespa.flags.custom.SharedHost;
 
 import java.util.List;
@@ -83,11 +83,17 @@ public class Flags {
             "Takes effect on the next run of RetiredExpirer.",
             HOSTNAME);
 
-    public static final UnboundListFlag<HostCapacity> TARGET_CAPACITY = defineListFlag(
-            "preprovision-capacity", List.of(), HostCapacity.class,
-            "List of node resources and their count that should be provisioned." +
-            "In a dynamically provisioned zone this specifies the unallocated (i.e. pre-provisioned) capacity. " +
-            "Otherwise it specifies the total (unallocated or not) capacity.",
+    public static final UnboundListFlag<ClusterCapacity> PREPROVISION_CAPACITY = defineListFlag(
+            "preprovision-capacity", List.of(), ClusterCapacity.class,
+            "Specifies the resources that ought to be immediately available for additional cluster " +
+            "allocations.  If the resources are not available, additional hosts will be provisioned. " +
+            "Only applies to dynamically provisioned zones.",
+            "Takes effect on next iteration of DynamicProvisioningMaintainer.");
+
+    public static final UnboundBooleanFlag COMPACT_PREPROVISION_CAPACITY = defineFeatureFlag(
+            "compact-preprovision-capacity", true,
+            "Whether preprovision capacity can be satisfied with available capacity on hosts with " +
+            "existing allocations.  Historically preprovision-capacity referred to empty hosts.",
             "Takes effect on next iteration of DynamicProvisioningMaintainer.");
 
     public static final UnboundJacksonFlag<SharedHost> SHARED_HOST = defineJacksonFlag(
diff --git a/flags/src/main/java/com/yahoo/vespa/flags/custom/ClusterCapacity.java b/flags/src/main/java/com/yahoo/vespa/flags/custom/ClusterCapacity.java
new file mode 100644
index 00000000000..8970d421681
--- /dev/null
+++ b/flags/src/main/java/com/yahoo/vespa/flags/custom/ClusterCapacity.java
@@ -0,0 +1,89 @@
+// Copyright 2019 Oath Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+package com.yahoo.vespa.flags.custom;
+
+import com.fasterxml.jackson.annotation.JsonCreator;
+import com.fasterxml.jackson.annotation.JsonGetter;
+import com.fasterxml.jackson.annotation.JsonIgnore;
+import com.fasterxml.jackson.annotation.JsonIgnoreProperties;
+import com.fasterxml.jackson.annotation.JsonInclude;
+import com.fasterxml.jackson.annotation.JsonProperty;
+
+import java.util.Objects;
+import java.util.Optional;
+
+/**
+ * @author freva
+ */
+// @Immutable
+@JsonIgnoreProperties(ignoreUnknown = true)
+@JsonInclude(value = JsonInclude.Include.NON_NULL)
+public class ClusterCapacity {
+    private final int count;
+    private final double vcpu;
+    private final double memoryGb;
+    private final double diskGb;
+    private final Optional<Double> bandwidthGbps;
+
+    @JsonCreator
+    public ClusterCapacity(@JsonProperty("count") int count,
+                           @JsonProperty("vcpu") double vcpu,
+                           @JsonProperty("memoryGb") double memoryGb,
+                           @JsonProperty("diskGb") double diskGb,
+                           @JsonProperty("bandwidthGbps") Double bandwidthGbps) {
+        this.count = (int) requireNonNegative("count", count);
+        this.vcpu = requireNonNegative("vcpu", vcpu);
+        this.memoryGb = requireNonNegative("memoryGb", memoryGb);
+        this.diskGb = requireNonNegative("diskGb", diskGb);
+        this.bandwidthGbps = Optional.ofNullable(bandwidthGbps);
+    }
+
+    /** Returns a new ClusterCapacity equal to {@code this}, but with the given count. */
+    public ClusterCapacity withCount(int count) {
+        return new ClusterCapacity(count, vcpu, memoryGb, diskGb, bandwidthGbps.orElse(null));
+    }
+
+    @JsonGetter("count") public int count() { return count; }
+    @JsonGetter("vcpu") public double vcpu() { return vcpu; }
+    @JsonGetter("memoryGb") public double memoryGb() { return memoryGb; }
+    @JsonGetter("diskGb") public double diskGb() { return diskGb; }
+    @JsonGetter("bandwidthGbps") public Double bandwidthGbpsOrNull() { return bandwidthGbps.orElse(null); }
+
+    @JsonIgnore
+    public double bandwidthGbps() { return bandwidthGbps.orElse(1.0); }
+
+    @Override
+    public String toString() {
+        return "ClusterCapacity{" +
+                "count=" + count +
+                ", vcpu=" + vcpu +
+                ", memoryGb=" + memoryGb +
+                ", diskGb=" + diskGb +
+                ", bandwidthGbps=" + bandwidthGbps +
+                '}';
+    }
+
+    @Override
+    public boolean equals(Object o) {
+        if (this == o) return true;
+        if (o == null || getClass() != o.getClass()) return false;
+        ClusterCapacity that = (ClusterCapacity) o;
+        return count == that.count &&
+                Double.compare(that.vcpu, vcpu) == 0 &&
+                Double.compare(that.memoryGb, memoryGb) == 0 &&
+                Double.compare(that.diskGb, diskGb) == 0 &&
+                ((bandwidthGbps.isEmpty() && that.bandwidthGbps.isEmpty()) ||
+                        ((bandwidthGbps.isPresent() && that.bandwidthGbps.isPresent() &&
+                                Double.compare(that.bandwidthGbps.get(), bandwidthGbps.get()) == 0)));
+    }
+
+    @Override
+    public int hashCode() {
+        return Objects.hash(count, vcpu, memoryGb, diskGb, bandwidthGbps);
+    }
+
+    private static double requireNonNegative(String name, double value) {
+        if (value < 0)
+            throw new IllegalArgumentException("'" + name + "' must be positive, was " + value);
+        return value;
+    }
+}
diff --git a/flags/src/main/java/com/yahoo/vespa/flags/custom/HostCapacity.java b/flags/src/main/java/com/yahoo/vespa/flags/custom/HostCapacity.java
deleted file mode 100644
index 947520ca2d7..00000000000
--- a/flags/src/main/java/com/yahoo/vespa/flags/custom/HostCapacity.java
+++ /dev/null
@@ -1,73 +0,0 @@
-// Copyright 2019 Oath Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
-package com.yahoo.vespa.flags.custom;
-
-import com.fasterxml.jackson.annotation.JsonIgnoreProperties;
-import com.fasterxml.jackson.annotation.JsonProperty;
-
-import java.util.Objects;
-
-/**
- * @author freva
- */
-@JsonIgnoreProperties(ignoreUnknown = true)
-public class HostCapacity {
-    @JsonProperty("vcpu")
-    private final double vcpu;
-
-    @JsonProperty("memoryGb")
-    private final double memoryGb;
-
-    @JsonProperty("diskGb")
-    private final double diskGb;
-
-    @JsonProperty("count")
-    private final int count;
-
-    public HostCapacity(@JsonProperty("vcpu") double vcpu,
-                        @JsonProperty("memoryGb") double memoryGb,
-                        @JsonProperty("diskGb") double diskGb,
-                        @JsonProperty("count") int count) {
-        this.vcpu = requirePositive("vcpu", vcpu);
-        this.memoryGb = requirePositive("memoryGb", memoryGb);
-        this.diskGb = requirePositive("diskGb", diskGb);
-        this.count = (int) requirePositive("count", count);
-    }
-
-    public double getVcpu() {
-        return vcpu;
-    }
-
-    public double getMemoryGb() {
-        return memoryGb;
-    }
-
-    public double getDiskGb() {
-        return diskGb;
-    }
-
-    public int getCount() {
-        return count;
-    }
-
-    private static double requirePositive(String name, double value) {
-        if (value <= 0)
-            throw new IllegalArgumentException("'" + name + "' must be positive, was " + value);
-        return value;
-    }
-
-    @Override
-    public boolean equals(Object o) {
-        if (this == o) return true;
-        if (o == null || getClass() != o.getClass()) return false;
-        HostCapacity that = (HostCapacity) o;
-        return Double.compare(that.vcpu, vcpu) == 0 &&
-                Double.compare(that.memoryGb, memoryGb) == 0 &&
-                Double.compare(that.diskGb, diskGb) == 0 &&
-                count == that.count;
-    }
-
-    @Override
-    public int hashCode() {
-        return Objects.hash(vcpu, memoryGb, diskGb, count);
-    }
-}
diff --git a/flags/src/test/java/com/yahoo/vespa/flags/custom/ClusterCapacityTest.java b/flags/src/test/java/com/yahoo/vespa/flags/custom/ClusterCapacityTest.java
new file mode 100644
index 00000000000..0258b562897
--- /dev/null
+++ b/flags/src/test/java/com/yahoo/vespa/flags/custom/ClusterCapacityTest.java
@@ -0,0 +1,41 @@
+// Copyright Verizon Media. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+package com.yahoo.vespa.flags.custom;
+
+import com.fasterxml.jackson.databind.ObjectMapper;
+import org.junit.Test;
+
+import java.io.IOException;
+
+import static org.junit.Assert.assertEquals;
+
+public class ClusterCapacityTest {
+    @Test
+    public void serialization() throws IOException {
+        ClusterCapacity clusterCapacity = new ClusterCapacity(7, 1.2, 3.4, 5.6, null);
+        ObjectMapper mapper = new ObjectMapper();
+        String json = mapper.writeValueAsString(clusterCapacity);
+        assertEquals("{\"count\":7,\"vcpu\":1.2,\"memoryGb\":3.4,\"diskGb\":5.6}", json);
+
+        ClusterCapacity deserialized = mapper.readValue(json, ClusterCapacity.class);
+        assertEquals(1.2, deserialized.vcpu(), 0.0001);
+        assertEquals(3.4, deserialized.memoryGb(), 0.0001);
+        assertEquals(5.6, deserialized.diskGb(), 0.0001);
+        assertEquals(1.0, deserialized.bandwidthGbps(), 0.0001);
+        assertEquals(7, deserialized.count());
+    }
+
+    @Test
+    public void serialization2() throws IOException {
+        ClusterCapacity clusterCapacity = new ClusterCapacity(7, 1.2, 3.4, 5.6, 2.3);
+        ObjectMapper mapper = new ObjectMapper();
+        String json = mapper.writeValueAsString(clusterCapacity);
+        assertEquals("{\"count\":7,\"vcpu\":1.2,\"memoryGb\":3.4,\"diskGb\":5.6,\"bandwidthGbps\":2.3}", json);
+
+        ClusterCapacity deserialized = mapper.readValue(json, ClusterCapacity.class);
+        assertEquals(1.2, deserialized.vcpu(), 0.0001);
+        assertEquals(3.4, deserialized.memoryGb(), 0.0001);
+        assertEquals(5.6, deserialized.diskGb(), 0.0001);
+        assertEquals(2.3, deserialized.bandwidthGbps(), 0.0001);
+        assertEquals(7, deserialized.count());
+    }
+}
\ No newline at end of file