Feedback-ID: ia2694551:Fastmail
Date: Thu, 16 Nov 2023 18:26:33 +0100
From: Alvaro Herrera <alvherre@alvh.no-ip.org>
To: Robert Haas <robertmhaas@gmail.com>
Cc: Andres Freund <andres@anarazel.de>,
	Peter Eisentraut <peter@eisentraut.org>, Dilip Kumar <dilipbalaut@gmail.com>,
	"pgsql-hackers@postgresql.org" <pgsql-hackers@postgresql.org>
Subject: Re: trying again to get incremental backup
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On 2023-Nov-16, Robert Haas wrote:

> On Thu, Nov 16, 2023 at 5:21 AM Alvaro Herrera <alvherre@alvh.no-ip.org> wrote:
> > I meant code like this
> >
> >         memcpy(&key.rlocator, rlocator, sizeof(RelFileLocator));
> >         key.forknum = forknum;
> >         entry = blockreftable_lookup(brtab->hash, key);
> 
> Ah, I hadn't thought about that. Another way of handling that might be
> to add = {0} to the declaration of key. But I can do the initializer
> thing too if you think it's better. I'm not sure if there's an
> argument that the initializer might optimize better.

I think the {0} initializer is good enough, given a comment to indicate
why.

> > It's not clear to me if WalSummarizerCtl->pending_lsn if fulfilling some
> > purpose or it's just a leftover from prior development.  I see it's only
> > read in an assertion ... Maybe if we think this cross-check is
> > important, it should be turned into an elog?  Otherwise, I'd remove it.
> 
> I've been thinking about that. One thing I'm not quite sure about
> though is introspection. Maybe there should be a function that shows
> summarized_tli and summarized_lsn from WalSummarizerData, and maybe it
> should expose pending_lsn too.

True.

-- 
Álvaro Herrera        Breisgau, Deutschland  —  https://www.EnterpriseDB.com/