Re: [HACKERS] Transactions involving multiple postgres foreign servers

On Thu, Dec 28, 2017 at 11:08 AM, Masahiko Sawada <sawada.mshk@gmail.com> wrote:
>
>> (1)
>> Why don't you use the existing global variable MyXactFlags instead of the new TransactionDidWrite?  Or, how about
usingXactLastRecEnd != 0 to determine the transaction did any writes?  When the transaction only modified temporary
tableson the local database and some data on one remote database, I think 2pc is unnecessary. 
>
> Perhaps we can use (XactLastRecEnd != 0 && markXidCommitted) to see if
> we did any writes on local node which requires the atomic commit. Will
> fix.
>

I haven't checked how much code it needs to track whether the local
transaction wrote anything. But probably we can post-pone this
optimization. If it's easy to incorporate, it's good to have in the
first set itself.

--
Best Wishes,
Ashutosh Bapat
EnterpriseDB Corporation
The Postgres Database Company