I have created a new instance compiler1003.puppet-diffs.eqiad.wmflabs and eventually deleted it after 35 minutes of puppet running on it.
I created it a second time and it is still slow https://horizon.wikimedia.org/project/instances/7ee33824-55f0-4c80-ba7f-c317bea301a3/ . The console shows errors such as :
/Stage[main]/Base::Environment/File[/etc/profile.d/field.sh]: Could not evaluate: Could not retrieve file metadata for puppet:///modules/base/environment/field.sh: execution expired
Sounds like an issue on the WMCS puppetmaster?