Re: Notes on lock table spilling

Alvaro Herrera <alvherre@dcc.uchile.cl> writes:

> Using Phantom Xids
> ==================
> The idea here is to use an approach similar to what we use now: mark the
> tuples with an Xid when it is locked.  A phantom Xid is a sort-of Xid,
> with multiple real Xids associated to it.  So we mark the tuple with the
> regular Xid the first time the share lock is acquired; if a second
> transaction wants to lock the tuple, it creates a new phantom Xid which
> "contains" the original Xid in the tuple and its own Xid, insert it into
> the phantom Xid table, and mark the tuple with that as Xmax.

That sounds like a fancy way to describe "make a linked list of lockers".

-- 
greg