Re: PATCH: Add 'pid' column to pg_replication_slots

On 2015-04-07 18:41:59 +0800, Craig Ringer wrote:
> @@ -331,8 +331,8 @@ ReplicationSlotAcquire(const char *name)
>                       volatile ReplicationSlot *vslot = s;
>
>                       SpinLockAcquire(&s->mutex);
> -                     active = vslot->active;
> -                     vslot->active = true;
> +                     active = vslot->active_pid != 0;
> +                     vslot->active_pid = MyProcPid;
>                       SpinLockRelease(&s->mutex);
>                       slot = s;
>                       break;

Uh. You're overwriting the existing pid here. Not good if the slot is
currently in use.

>                       namecpy(&plugin, &slot->data.plugin);
>
> -                     active = slot->active;
> +                     active_pid = slot->active_pid != 0;

That doesn't look right.

I don't really like the 'pid' field for pg_replication_slots. About
naming it 'active_in' or such?