Reuse allocation decisions

During deployment we first prepare the application on one config server
then notifies the other config servers (by setting state=PREPARED)
that they should load it. That will cause allocation requests against
the node repo to be done once over on the those config servers.
These simultaneous requests against the node repo may cause ut
to time out waiting for the node repo's application lock if
these requests take a somewhat long time.

This change reads existing allocations instead of redoing
allocation requests against the node repo. The existing allocation
is saved (on the first config server) before state=PREPARED is set.

1 files changed, 5 insertions, 0 deletions

diff --git a/vespajlib/src/main/java/com/yahoo/lang/SettableOptional.java b/vespajlib/src/main/java/com/yahoo/lang/SettableOptional.java
index db5dd76c124..e83a6c3f308 100644
--- a/vespajlib/src/main/java/com/yahoo/lang/SettableOptional.java
+++ b/vespajlib/src/main/java/com/yahoo/lang/SettableOptional.java
@@ -19,6 +19,11 @@ public final class SettableOptional<T> {
     /** Creates a new settable optional with the given value */
     public SettableOptional(T value) { this.value = value; }
 
+    /** Creates a new settable optional with the given value, or an empty */
+    public SettableOptional(Optional<T> value) {
+        this.value = value.isPresent() ? value.get() : null;
+    }
+
     public boolean isPresent() {
         return value != null;
     }