My Prod database has taken almost 1 hour to shutdown after the stop command

Hello Experts,

      My production database of size around 1TB in distributed system with 4+2 nodes. Last week, we tried to bring down the DB for OS patches, the HANA DB took almost 45 mins to come down.

       The BW application server was down few mins before we issue the command in DB side. I am aware of the internal process during shutdown. But my question is any one could able to explain is there is any best practices before issuing the DB stop command in HANA.

     I would like to effeciently handle the DB outage.  Your thoughts will be appreciated.

Regards

Suresh