Re: Logical Replication WIP

On 1/22/17 8:11 PM, Petr Jelinek wrote:
> 0001 - Changes the libpqrcv_connect to use async libpq api so that it
> won't get stuck forever in case of connect is stuck. This is preexisting
> bug that also affects walreceiver but it's less visible there as there
> is no SQL interface to initiate connection there.

Probably a mistake here:

+ case PGRES_POLLING_READING:
+ extra_flag = WL_SOCKET_READABLE;
+ /* pass through */
+ case PGRES_POLLING_WRITING:
+ extra_flag = WL_SOCKET_WRITEABLE;

extra_flag gets overwritten in the reading case.

Please elaborate in the commit message what this change is for.

> 0002 - Close replication connection when CREATE SUBSCRIPTION gets
> canceled (otherwise walsender on the other side may stay in idle in
> transaction state).

committed

> 0003 - Fixes buffer initialization in walsender that I found when
> testing the above two. This one should be back-patched to 9.4 since it's
> broken since then.

Can you explain more in which code path this problem occurs?

I think we should get rid of the global variables and give each function
its own buffer that it initializes the first time through. Otherwise
we'll keep having to worry about this.

> 0004 - Fixes the foreign key issue reported by Thom Brown and also adds
> tests for FK and trigger handling.

I think the trigger handing should go into execReplication.c.

> 0005 - Adds support for renaming publications and subscriptions.

Could those not be handled in the generic rename support in
ExecRenameStmt()?

--
Peter Eisentraut http://www.2ndQuadrant.com/
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