collection, triggered in background when I/O subsystem is
idle. If background_gc=on, it will turn on the garbage
collection and if background_gc=off, garbage collection
- will be truned off.
+ will be truned off. If background_gc=sync, it will turn
+ on synchronous garbage collection running in background.
Default value for this option is on. So garbage
collection is on by default.
disable_roll_forward Disable the roll-forward recovery routine