Comment # 15 on bug 1198668 from Michal Koutn���

(In reply to Tejas Guruswamy from comment #14)
> > systemctl show -p Before purge-kernels.service 
> Before=shutdown.target YaST2-Second-Stage.service multi-user.target
> YaST2-Firstboot.service

I'm not sure purge-kernels.service:Before=multi-user.target would cause the
'waiting for boot to finish' (actually is it a verbatim message? I can't grep
it in sources). (The YaST2* service may cause it but it's not what the original
report was about AFAICT.) 

> Because of the '[Install] WantedBy=multi-user.target', it is getting an
> implicit Before=multi-user.target.
> 
> Is After=multi-user.target ok to fix this? Does it even need an [Install]
> section at all?

You need some other unit to pull-in purge-kernels.service into the boot
transaction.

(In reply to Franck Bui from comment #13)
> I don't think Type=exec is the correct fix here. If there's anything wrong
> with purge-kernels.service ordering constraints then they should be fixed
> instead of tweaking the type of the service itself.

It IMO depends whether the mere launch of the service is important or someone
relies on old kernels being truly gone (i.e. wait for purge-kernels to finish).

> Maybe it's more related to slow IOs or such.

Yes, in that case the Type=exec workaround would prove ineffective. So I wonder
when we can get feedback on the maint-request.