Creating a view-counter for the current page

Help / Discuss
1

Hello, Im currently trying to create an small view-counter that simply shows the total number of views of the current page. I want to create it with the least amount of work and as few code lines as possible and we also do not want to add an analytics server in our organisation.
So I try to use the integrated statistics on a test server.

For that I have some questions: It is warned that the integrated statistics have an performance penalty as every view is counted into the database. Can someone give more information of that, how huge is the performance impact? Is it really huge?
We currently have an very much oversized VM for the XWiki server with much more CPU and RAM as XWiki can possibly use for our only 500 users but of course I don’t want lower the performance noticeable to the users.

Also how much does it bloat the database? Is that significantly? Are there ways to reset the statistics at a later point to get rid of it in case it bloated because of enabled statistics?

And also some velocity scripting questions:
The most basic reduced working code I found yet is this:

{{velocity}}
#if ($xwiki.statsService.enabledForCurrentWiki)
  #set ($scope = $xwiki.criteriaService.scopeFactory.ALL_PAGES)
  #set ($period = $xwiki.criteriaService.periodFactory.ALL_TIME)
  #set ($interval = $xwiki.criteriaService.rangeFactory.createHeadRange(50))
  #set ($stats = $xwiki.statsService.getDocumentStatistics('view', $scope, $period, $interval))
  #foreach($item in $stats)
    #set($docStats = $xwiki.getDocument($item.name))
    #if ($docStats)
      * $item.name $item.pageViews
    #end
  #end
#end
{{/velocity}}

However as a scope I only require the current page as I just want to see the current page views. Sadly I cannot find any information about the available scopes of the $xwiki.criteriaService.scopeFactory
Is the scopeFactory even the right approach for that simple thing I want to achive or is there an simpler way?

Thank you very much in advance!