> My postgre version is 9.4.9, and I face a space issue.
Latest in 9.4 is 9.4.17, so you're missing about two years of bug fixes.
> Every time I restart postgre server, it generates a new history file:
That's strange -- it shouldn't happen ... sounds like you're causing a
crash each time you restart. Are you using immediate mode in shutdown
maybe? If so, don't; use fast mode instead.
Álvaro Herrera https://www.2ndQuadrant.com/
PostgreSQL Development, 24x7 Support, Remote DBA, Training & Services