Re: Bugs in TOAST handling, OID assignment and redo recovery

On 2018-Apr-11, Peter Eisentraut wrote:

> On 4/10/18 06:29, Pavan Deolasee wrote:
> > One of our 2ndQuadrant support customers recently reported a sudden rush
> > of TOAST errors post a crash recovery, nearly causing an outage. Most
> > errors read like this:
> >
> > ERROR: unexpected chunk number 0 (expected 1) for toast value nnnn
>
> While researching this, I found that the terminology in this code is
> quite inconsistent. It talks about chunks ids, chunk indexes, chunk
> numbers, etc. seemingly interchangeably. The above error is actually
> about the chunk_seq, not about the chunk_id, as one might think.
>
> The attached patch is my attempt to clean this up a bit. Thoughts?

I didn't review your patch carefully, but +1 on the idea. By all means
let's not forget this for pg12.

--
Álvaro Herrera https://www.2ndQuadrant.com/
PostgreSQL Development, 24x7 Support, Remote DBA, Training & Services