Re: ECPG FETCH readahead - Mailing list pgsql-hackers

From Michael Meskes
Subject Re: ECPG FETCH readahead
Date
Msg-id 20120424081714.GA12034@feivel.credativ.lan
Whole thread Raw
In response to Re: ECPG FETCH readahead  (Boszormenyi Zoltan <zb@cybertec.at>)
Responses Re: ECPG FETCH readahead  (Boszormenyi Zoltan <zb@cybertec.at>)
List pgsql-hackers
> OK, I will implement #2. Another question popped up: what to do
> with FETCH ALL? The current readahead window size or temporarily
> bumping it to say some tens of thousands can be used. We may not
> know how much is the "all records". This, although lowers performance,
> saves memory.

I would say doing a large fetch in two or three batches won't cost too much in
terms of performance.

> Please, don't apply this patch yet. I discovered a rather big hole
> that can confuse the cursor position tracking if you do this:
> ...
> That will also need a new round of review. Sorry for that.

No problem, better to find it now instead of after release.

Anyway, I moved the patch to 2012-next (I hope I did it correctly) so 2012-1
can be closed. Let's try to get this patch done in the next commit fest.

Michael
--
Michael Meskes
Michael at Fam-Meskes dot De, Michael at Meskes dot (De|Com|Net|Org)
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