Re: [PATCH 11/14] Introduce wal decoding via catalog timetravel

Andres Freund <andres@2ndquadrant.com>

From: Andres Freund <andres@2ndquadrant.com>
To: Steve Singer <steve@ssinger.info>
Cc: pgsql-hackers@postgresql.org
Date: 2012-12-03T12:42:00Z
Lists: pgsql-hackers
On 2012-12-03 13:22:12 +0100, Andres Freund wrote:
> Hi Steve,
>
> On 2012-12-02 21:52:08 -0500, Steve Singer wrote:
> > On 12-11-14 08:17 PM, Andres Freund wrote:
> >
> > I am getting errors like the following when I try to use either your
> > test_decoding plugin or my own (which does even less than yours)
> >
> >
> > LOG:  database system is ready to accept connections
> > LOG:  autovacuum launcher started
> > WARNING:  connecting to
> > WARNING:  Initiating logical rep
> > LOG:  computed new xmin: 773
> > LOG:  start reading from 0/17F5D58, scrolled back to 0/17F4000
> > LOG:  got new xmin 773 at 25124280
> > LOG:  found initial snapshot (via running xacts). Done: 1
> > WARNING:  reached consistent point, stopping!
> > WARNING:  Starting logical replication
> > LOG:  start reading from 0/17F5D58, scrolled back to 0/17F4000
> > LOG:  found initial snapshot (via running xacts). Done: 1
> > FATAL:  cannot read pg_class without having selected a database
> > TRAP: FailedAssertion("!(SHMQueueEmpty(&(MyProc->myProcLocks[i])))", File:
> > "proc.c", Line: 759)
> >
> > This seems to be happening under the calls at
> > reorderbuffer.c:832    if (!SnapBuildHasCatalogChanges(NULL, xid,
> > &change->relnode))
>
> Two things:
> 1) Which exact options are you using for pg_receivellog? Not "-d
> replication" by any chance?

This seems to produce exactly that kind off error messages. I added some
error checking around that. Pushed.

Thanks!

Andres Freund

--
 Andres Freund	                   http://www.2ndQuadrant.com/
 PostgreSQL Development, 24x7 Support, Training & Services


Commits

Same data as JSON: GET /api/v1/messages/:b64id/commits the thread's linked commits as JSON, with link sources. API reference →
  1. Background worker processes

  2. Rearrange storage of data in xl_running_xacts.

  3. Basic binary heap implementation.

  4. Embedded list interface

  5. Refactor xlog.c to create src/backend/postmaster/startup.c