[nmader]

Every 30 seconds may cause you to lag if you are saving a bunch, however perhaps something like this:

pawn Код:

OnPlayerConnect
{
    SetTimer("SavePlayer", 30000, true);
}

pawn Код:

forward SavePlayer(playerid);

pawn Код:

public SavePlayer(playerid)
{
    //What is saving every 30 seconds
}

pawn Код:

OnGameModeExit
{
    SavePlayer(playerid);
}

NOTE: Not tested

EDIT: Also, your signature caught my eye, you spelled sever it should be server.