Description of problem:
On a scaled environment with thousands of pools, katello:import_subscriptions (called e.g. during an upgrade) does call

Katello::Pool.import_all

that traverses over each and every pool and imports hosts and namely Activation Keys from candlepin. That means, a call like:

/candlepin/owners/RedHat/activation_keys/?include=id&include=pools.pool.id

is repeatedly requested for each and every pool.

If such a request takes longer, overall upgrade time is redundantly increased.

I propose a simple patch to query that once and pass the keys to the proper routine.


Version-Release number of selected component (if applicable):
Sat 6.4.2


How reproducible:
100%


Steps to Reproduce:
1. Have a system with some AKs and more pools in manifest - the more the better.

2. in one terminal:
tail -f /var/log/candlepin/candlepin.log | grep "/activation_keys/?include=id&include=pools.pool.id"

3. in 2nd terminal:
foreman-rake katello:import_subscriptions

4. count number of lines printed in the 1st terminal


Actual results:
4. shows as many logs / queries to candlepin as the number of pools is (plus one, I think).


Expected results:
4. to show just 1 or 2 such queries



Additional info:
Patch:

--- /opt/theforeman/tfm/root/usr/share/gems/gems/katello-3.7.0.46/app/models/katello/glue/candlepin/candlepin_object.rb.orig	2019-02-27 15:43:28.390609472 +0100
+++ /opt/theforeman/tfm/root/usr/share/gems/gems/katello-3.7.0.46/app/models/katello/glue/candlepin/candlepin_object.rb.new	2019-02-27 15:44:07.067642277 +0100
@@ -37,12 +37,13 @@ module Katello
 
         organizations.each do |org|
           candlepin_ids = import_candlepin_ids(org)
+          keys = Resources::Candlepin::ActivationKey.get(nil, "?include=id&include=pools.pool.id", org.label)
 
           objects = self.in_organization(org)
           objects.each do |item|
             if candlepin_ids.include?(item.cp_id)
               item.import_data
-              item.import_managed_associations if import_managed_associations && item.respond_to?(:import_managed_associations)
+              item.import_managed_associations(keys) if import_managed_associations && item.respond_to?(:import_managed_associations)
             else
               item.destroy
             end

--- /opt/theforeman/tfm/root/usr/share/gems/gems/katello-3.7.0.46/app/models/katello/glue/candlepin/pool.rb.orig	2019-02-27 15:44:38.758669157 +0100
+++ /opt/theforeman/tfm/root/usr/share/gems/gems/katello-3.7.0.46/app/models/katello/glue/candlepin/pool.rb.new 	2019-02-27 15:50:58.411991079 +0100
@@ -181,17 +181,16 @@ module Katello
         Katello::SubscriptionFacetPool.where(:pool_id => self.id, :subscription_facet_id => entries_to_remove).delete_all
       end
 
-      def import_managed_associations
+      def import_managed_associations(keys)
         import_hosts
-        create_activation_key_associations
+        create_activation_key_associations(keys)
       end
 
       def hosts
         ::Host.where(:id => self.subscription_facets.pluck(:host_id))
       end
 
-      def create_activation_key_associations
-        keys = Resources::Candlepin::ActivationKey.get(nil, "?include=id&include=pools.pool.id", organization.label)
+      def create_activation_key_associations(keys)
         activation_key_ids = keys.collect do |key|
           key['id'] if key['pools'].present? && key['pools'].any? { |pool| pool['pool'].try(:[], 'id') == cp_id }
         end