configureable node disk space buffer considered during gear moves

Author: sallyom

broker/conf/broker.conf

@@ -217,6 +217,12 @@ DEFAULT_REGION_NAME=""
 # Allow region selection when creating applications. Default is true
 ALLOW_REGION_SELECTION="true"
 
+# Minimum Node Disk Buffer Percentage
+#
+# When moving a gear to a new node, ensure that after a move this percentage
+# of free disk space will remain on the new node.
+MIN_NODE_DISK_BUFFER="5"
+
 # Normalize logins / usernames according to specified method(s) in OpenShift::Username;
 # e.g. when set to "lowercase", a user logging in as "JDoe" is the same as "jdoe".
 # WARNING: nothing is done automatically to update existing non-normalized logins,

broker/config/environments/development.rb

@@ -123,6 +123,7 @@
     :app_advertise_https => conf.get_bool("APP_ADVERTISE_HTTPS", false),
     :auth_user_lookup_only => conf.get_bool("AUTH_USER_LOOKUP_ONLY", false),
     :auth_user_lookup_fail_msg => conf.get("AUTH_USER_LOOKUP_FAIL_MESSAGE", "This cluster is configured for user lookup only. Please contact your system administrator for provisioning your user account."),
+    :min_node_disk_buffer => (conf.get("MIN_NODE_DISK_BUFFER", "5")).to_i
   }
 
   config.auth = {

broker/config/environments/production.rb

@@ -112,6 +112,7 @@
     :app_advertise_https => conf.get_bool("APP_ADVERTISE_HTTPS", false),
     :auth_user_lookup_only => conf.get_bool("AUTH_USER_LOOKUP_ONLY", false),
     :auth_user_lookup_fail_msg => conf.get("AUTH_USER_LOOKUP_FAIL_MESSAGE", "This cluster is configured for user lookup only. Please contact your system administrator for provisioning your user account."),
+    :min_node_disk_buffer => (conf.get("MIN_NODE_DISK_BUFFER", "5")).to_i
   }
 
   config.auth = {

broker/config/environments/test.rb

@@ -121,6 +121,7 @@
     :app_advertise_https => conf.get_bool("APP_ADVERTISE_HTTPS", false),
     :auth_user_lookup_only => conf.get_bool("AUTH_USER_LOOKUP_ONLY", false),
     :auth_user_lookup_fail_msg => conf.get("AUTH_USER_LOOKUP_FAIL_MESSAGE", "This cluster is configured for user lookup only. Please contact your system administrator for provisioning your user account."),
+    :min_node_disk_buffer => (conf.get("MIN_NODE_DISK_BUFFER", "5")).to_i
   }
 
   config.auth = {

plugins/msg-broker/mcollective/lib/openshift/mcollective_application_container_proxy.rb

@@ -2413,11 +2413,13 @@ def rsync_destination_container(gear, destination_container, destination_distric
       log_debug "DEBUG: Gear platform is '#{platform}'"
       destination_avail_space = destination_container.get_node_disk_free
       destination_total_space = destination_container.get_node_total_size
+      min_node_disk_buffer = Rails.application.config.openshift[:min_node_disk_buffer].to_f
 
       # check here to make sure addition of gear to destination_container
       # will not result in > 95% full destination_container
-      if (destination_avail_space - source_used_blocks.to_f)/destination_total_space < 0.05
-        raise OpenShift::NodeUnavailableException.new("Gear '#{gear.uuid}' cannot be moved to '#{destination_container.id}'.  Not enough disk space, node would be > 95% full after move.", 140)
+      if (destination_avail_space - source_used_blocks.to_f)/destination_total_space < (min_node_disk_buffer/100)
+        max_percentage = sprintf('%.0f', 100 - min_node_disk_buffer)
+        raise OpenShift::NodeUnavailableException.new("Gear '#{gear.uuid}' cannot be moved to '#{destination_container.id}'.  Not enough disk space, node would be > #{max_percentage}% full after move.", 140)
       end
 
       log_debug "DEBUG: Creating new account for gear '#{gear.uuid}' on #{destination_container.id}"