Comment # 2 on bug 1117225 from Michael Andres

Sorry Sven, but I've got no clue. zypper ref, ar and rr do not use rpm at all
(only package install and remove actions do). You could open a terminal window
and run `tail -f /var/log/zypper.log` in it. This way you can estimate when a
zypper command ends. It's usually looks like this (releasing the zypp lock,
closing the rpm database):

> 2018-11-26 09:34:05 <1> fibonacci(1126) [zypp] ZYppFactory.cc(_closeLockFile):186 Close lockfile /var/run/zypp.pid
> 2018-11-26 09:34:05 <1> fibonacci(1126) [zypp] ZYppFactory.cc(~ZYpp):318 ZYpp is off...
> 2018-11-26 09:34:05 <1> fibonacci(1126) [zypp] RpmDb.cc(closeDatabase):720 Calling closeDatabase: RpmDb[V4(X--)V3(---): '(/)/var/lib/rpm']
> 2018-11-26 09:34:05 <1> fibonacci(1126) [zypp] librpmDb.cc(blockAccess):328 Block access
> 2018-11-26 09:34:05 <1> fibonacci(1126) [zypp] RpmDb.cc(closeDatabase):751 closeDatabase: RpmDb[NO_INIT]
> 2018-11-26 09:34:05 <1> fibonacci(1126) [zypp] TargetImpl.cc(~TargetImpl):817 Targets closed
> 2018-11-26 09:34:05 <1> fibonacci(1126) [zypp] RpmDb.cc(~RpmDb):254 ~RpmDb()
> 2018-11-26 09:34:05 <1> fibonacci(1126) [zypp] RpmDb.cc(~RpmDb):257 ~RpmDb() end

Running `top` in an other window might help to identify a program starting
after zypper/rpm ended.

I'm not familiar with zsh, but maybe your prompt definition has some command
embedded, which causes the delay (similar to bash $PROMPT_COMMAND).

Do other shells (bash, sh,... ) show th same symptoms?