Squid/pulp migration



First let me thank you for the great support I received in in this forum until now.
I read the documentation here Foreman :: Plugin Manuals and it says:

The path /var/spool/squid/ is used as a temporary location for some types of repository syncs and may grow to consume 10s of GB of space before the files are migrated to /var/lib/pulp.

I’m wondering how/when this “migration” from squid to pulp happens. Is there something that can/should be tuned for performance?