Re: Asynchronous execution on FDW

On 07/02/2015 08:48 AM, Kyotaro HORIGUCHI wrote:
> - It was a problem when to give the first kick for async exec. It
>    is not in ExecInit phase, and ExecProc phase does not fit,
>    too. An extra phase ExecPreProc or something is too
>    invasive. So I tried "pre-exec callback".
>
>    Any init-node can register callbacks on their turn, then the
>    registerd callbacks are called just before ExecProc phase in
>    executor. The first patch adds functions and structs to enable
>    this.

At a quick glance, I think this has all the same problems as starting 
the execution at ExecInit phase. The correct way to do this is to kick 
off the queries in the first IterateForeignScan() call. You said that 
"ExecProc phase does not fit" - why not?

- Heikki