NB! It seems this console command is not compatible with CS2.
Command Profile

HOST_FLUSH_THRESHOLD

CS:GO

This command will set the memory theshold for the which host should flush caches between server instances. When below this value, the caches will be flushed.

Syntax
host_flush_threshold [Threshold]

Description

This command will set the memory theshold for the which host should flush caches between server instances. When below this value, the caches will be flushed.

Syntax And Arguments

host_flush_threshold [Threshold]
Threshold The threshold that the caches should be flushed under.