Dear Amit,
>
> Won't it be possible to achieve the same thing if we just save
> (serialize) the highest xid among all running xacts?
>
Indeed, here is an updated version.
Since the array in xl_running_xact is not ordered, entries of it must be seeked
and found the highest one.
Best Regards,
Hayato Kuroda
FUJITSU LIMITED
https://www.fujitsu.com/