my %tasks = (
    templog => {
        interval => 5, # seconds
        code => sub {
            if (-e $templog) { ... } else { ... }
        },
    },
    backup => {
        interval => 2 * 60 * 60, # 2h
        code => \&DB_Backup,
    },
);
while (1) {
    for (keys %tasks) {
        my $since = time - ($tasks{$_}{last} || time);
        if ($since >= $tasks{$_}{interval}) {
            $tasks{$_}{code}->();
            $tasks{$_}{last} = time;
            CheckTS(); # Or put this in each sub { }
        }
    }
    sleep 1; # See note
}