Re: [PATCH 02/14] Add support for a generic wal reading facility dubbed XLogReader

On 2012-11-15 16:22:56 +0200, Heikki Linnakangas wrote:
> On 15.11.2012 03:17, Andres Freund wrote:
> >
> >Features:
> >- streaming reading/writing
> >- filtering
> >- reassembly of records
> >
> >Reusing the ReadRecord infrastructure in situations where the code that wants
> >to do so is not tightly integrated into xlog.c is rather hard and would require
> >changes to rather integral parts of the recovery code which doesn't seem to be
> >a good idea.
> >
> >Missing:
> >- "compressing" the stream when removing uninteresting records
> >- writing out correct CRCs
> >- separating reader/writer
>
> I'm disappointed to see that there has been no progress on this patch since
> last commitfest. I thought we agreed on the approach I championed for here:
> http://archives.postgresql.org/pgsql-hackers/2012-09/msg00636.php. There
> wasn't much work left to finish that, I believe.

While I still think my approach is superior at this point I have
accepted that I haven't convinced anybody of that. I plan to port over
what I have submitted to Alvaro's version of your patch.

I have actually started that but I simply couldn't finish it in
time. The approach for porting I took didn't work all that well and I
plan to restart doing that after doing some review work.

> Are you going to continue working on this?

"this" being my version of XlogReader? No. The patch above is unchanged
except some very minor rebasing to recent wal changes by Tom. The reason
its included in the series is simply that I haven't gotten rid of it yet
and the subsequent patches needed it. I do plan to continue working on a
rebased xlogdump version if nobody beats me to it (please do beat me!).

Ok?

The cover letter said:

> * Add support for a generic wal reading facility dubbed XLogReader
> There's some discussion about whats the best way to implement this in a
> separate CF topic.
> (unchanged)

I should have folded that in into the patch description, sorry.

Greetings,

Andres

--
Andres Freund http://www.2ndQuadrant.com/
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