PostgreSQL Timezone and Brazilian DST

Hi!

Using PostgreSQL 9.3.10 x86_64 Oracle EL7 compiled by gcc (GCC) 4.8.3
20140911, installed using yum repository.

In postgresql.conf, I do have:

timezone="America/Sao_Paulo"

Since DST is in place in Brazil, it is enough to "systemctl reload
postgresql-9.3" to make it effective?
Or a complete restart is required?

Thanks,

--
Atenciosamente,

Edson Carlos Ericksson Richter