PostgreSQL 12 High Availability Cookbook - Third Edition

How it works...

We begin by activating (-a y) the VG_POSTGRES/LV_DATA volume with lvchange. This is like vgchange, but only affects the named volume, instead of every volume in the named group. We used this command merely to demonstrate that either command will work for our stack, especially since there is only one volume to activate.

The next three steps involve a simple calculation, but it deserves some explanation. The main feature we want to exploit here is the count of allocation groups. Each allocation group can be addressed independently when making filesystem modifications. Presumably, this enhances performance in several different categories since it reduces allocation table contention.

To reach our desired number, we start with ...