What is the usage of the Flow database that is required in the installation

[ocampov]

We have a running instance of Flow on a Redhat server and a remote postgres db.

My question here is:

How or in which cases Flow uses its own database,

I have Flow connected to the foundation database to do some queries.

But it seems that is not using his own database to store or do high loads,

I want to know if it makes no difference to have the Flow database installed on the same local server as Flow.

I have read the documentation and it mentions the local installation as the default option.

[VladimirN]

Update: Ok, so it's ThingWorx Flow.

[ocampov]

Yes is Thingworx Flow.

In the installation process it requires its own db, 

I want the understand the usage of that db and if it makes any sense have it on a separate server or is better just to have in the same physical server as the documentation default process mentions.