@Override
    public long activate() {
        prepare();

        validateSessionStatus(session);

        waitForResourcesOrTimeout(params.get(), session, provisioner);

        ApplicationId applicationId = session.getApplicationId();
        try (ActionTimer timer = applicationRepository.timerFor(applicationId, ConfigServerMetrics.DEPLOYMENT_ACTIVATE_MILLIS.baseName())) {
            TimeoutBudget timeoutBudget = params.get().getTimeoutBudget();
            timeoutBudget.assertNotTimedOut(() -> "Timeout exceeded when trying to activate '" + applicationId + "'");

            Activation activation = applicationRepository.activate(session, applicationId, tenant, params.get().isBootstrap(), params.get().force());
            waitForActivation(applicationId, timeoutBudget, activation);
            restartServicesIfNeeded(applicationId);
            storeReindexing(applicationId);

            return session.getMetaData().getGeneration();
        }
    }
Activates this. If it is not already prepared, this will call prepare first.
configserver/src/main/java/com/yahoo/vespa/config/server/deploy/Deployment.java