save the following file somewhere and source it in your bashrc or  save it directly to /etc/profile.d/bash_history or smth

since it saves the bash history in /var/cache/bash/history/  (in one global and seperate files for each tty)

first time you run it it might ask for a sudo password  (or you can create the folder manually by hand :

sudo mkdir -p /var/cache/bash/history/

sudo chmod -R 777 $_

the script: (needs some work, so feel free to contribute, ill put it on github soon aswell if you prefer to contribute that way)

#!/usr/bin/env bash
# ############################################################################
# # PATH: /opt/local/config/rc/bash						   AUTHOR:Hoefkens.j@gmail.com
# # FILE: 311_history.conf
# ############################################################################
#
HISTFOLDER="/var/cache/bash/history"
HISTSIZE=-1
HISTFILESIZE=$HISTSIZE
HISTCONTROL=''
HISTFILE="$HISTFOLDER/history.$$"
HISTS="$HISTFOLDER/history.[0-9]*"
GLOBHIST="$HISTFOLDER/history.glob"
[[ ! -e "$HISTFOLDER" ]] && sudo mkdir -p "$HISTFOLDER" && sudo chmod 777 "$HISTFOLDER" && sudo chown 1:100  "$HISTFOLDER" 
[[ ! -f "$GLOBHIST" ]] && touch "$GLOBHIST" && chmod 777 "$GLOBHIST"
[[ -f "$HISTFILE" ]] && cat "$HISTFILE" >> "$GLOBHIST" && rm -f "$HISTFILE"
[[ ! -f "$HISTFILE" ]] && touch "$HISTFILE" && chmod 777 "$HISTFILE" 
for HIST in $( ls $HISTS) ; do
	cat "$HIST" >> "$HISTFILE" 2>/dev/null
done
sudo chmod -R 777 "$HISTFOLDER" && sudo chown -R 1:100  "$HISTFOLDER"


_bash_history_sync() {
    builtin history -a  "$HISTFILE"       
    builtin history -a  "$GLOBHIST"       
    builtin history -c         #3
    builtin history -r $GLOBHIST
    builtin history -r $HISTFILE    
}

history() {                  #5
    _bash_history_sync
    builtin history "$@"
}

PROMPT_COMMAND=_bash_history_sync

current status of my bash history: (kindof proof that it works :D))