B #3269: onedb purge-done eat too much RAM (#3376)

* Process done VMs in pages, instead of all together
    * Add new method to iterate over pages
    * Add new CLI paramter to specify pages size

src/oca/ruby/opennebula/pool.rb

@@ -233,10 +233,12 @@ module OpenNebula
 
         # Gets a hash from a info page from pool
         # size:: nil => default page size
-        #        > 0 => page size    
+        #        > 0 => page size
         # current first element of the page
+        # extended true to get extended information
+        # state state of the objects
         # hash:: return page as a hash
-        def get_page(size, current, extended = false)
+        def get_page(size, current, extended = false, state = -1)
             rc = nil
 
             if PAGINATED_POOLS.include?(@pool_name)
@@ -249,19 +251,43 @@ module OpenNebula
                 end
 
                 size = OpenNebula.pool_page_size if (!size || size == 0)
-                rc   = @client.call(method, @user_id, current, -size, -1)
+                rc   = @client.call(method, @user_id, current, -size, state)
 
                 initialize_xml(rc, @pool_name)
             else
                 rc = info
             end
 
-            return rc 
+            return rc
+        end
+
+        # Iterates over pool pages
+        # size:: nil => default page size
+        #        > 0 => page size
+        # state state of objects
+        # delete true to take always the first page
+        def each_page(size, state = -1, extended = false, delete = false)
+            current = 0
+            element = @pool_name.split('_')[0]
+            page    = OpenNebula::XMLElement.new
+
+            loop do
+                page.initialize_xml(get_page(size, current, extended, state),
+                                             @pool_name)
+
+                break if page["//#{element}"].nil?
+
+                page.each("//#{element}") do |obj|
+                    yield(obj)
+                end
+
+                current += size unless delete
+            end
         end
 
         # Return true if pool is paginated
         def is_paginated?
-            PAGINATED_POOLS.include?(@pool_name) 
+            PAGINATED_POOLS.include?(@pool_name)
         end
     end
 end

src/onedb/onedb

@@ -291,6 +291,14 @@ DELETE= {
     :description => "Delete all matched xpaths"
 }
 
+PAGES = {
+    :name => 'pages',
+    :short => '-p pages',
+    :large => '--pages pages',
+    :description => 'Nummber of pages to purge VMs',
+    :format => Integer
+}
+
 cmd=CommandParser::CmdParser.new(ARGV) do
     description <<-EOT.unindent
         This command enables the user to manage the OpenNebula database. It
@@ -500,7 +508,7 @@ cmd=CommandParser::CmdParser.new(ARGV) do
     EOT
 
     command :'purge-done', purge_done_desc,
-            :options => [START_TIME, END_TIME] do
+            :options => [START_TIME, END_TIME, PAGES] do
         begin
             action = OneDBLive.new
             action.purge_done_vm(options)

src/onedb/onedb_live.rb

@@ -4,7 +4,8 @@ require 'base64'
 
 class OneDBLive
 
-    EDITOR_PATH='/bin/vi'
+    EDITOR_PATH = '/bin/vi'
+    PAGES       = 0
 
     def initialize
         @client = nil
@@ -206,30 +207,23 @@ class OneDBLive
     end
 
     def purge_done_vm(options = {})
-        vmpool = OpenNebula::VirtualMachinePool.new(client)
-        vmpool.info(OpenNebula::Pool::INFO_ALL,
-                    -1,
-                    -1,
-                    OpenNebula::VirtualMachine::VM_STATE.index('DONE'))
-
-        ops = {
-            start_time: 0,
-            end_time: Time.now
-        }.merge(options)
-
+        ops         = { :start_time => 0,
+                        :end_time   => Time.now,
+                        :pages      => PAGES }.merge(options)
+        vmpool      = OpenNebula::VirtualMachinePool.new(client)
         start_time  = ops[:start_time].to_i
         end_time    = ops[:end_time].to_i
+        done        = OpenNebula::VirtualMachine::VM_STATE.index('DONE')
 
-        last_id = vmpool["/VM_POOL/VM[last()]/ID"]
+        vmpool.each_page(ops[:pages], done, false, true) do |obj|
+            print "VM with ID: #{obj['ID']} purged \r"
 
-        vmpool.each do |vm|
-            print percentage_line(vm.id, last_id, true)
+            time = obj['ETIME'].to_i
 
-            time = vm["ETIME"].to_i
             next unless time >= start_time && time < end_time
 
-            delete("vm_pool", "oid = #{vm.id}", false)
-            delete("history", "vid = #{vm.id}", false)
+            delete('vm_pool', "oid = #{obj['ID']}", false)
+            delete('history', "vid = #{obj['ID']}", false)
         end
     end