Hi hackers,
I noticed that the comments regarding bit layouts for varlena headers
in postgres.h are somewhat misleading. For instance, when reading:
```
00xx 4-byte length word, aligned, uncompressed data (up to 1G)
```
... one can assume this is a 00xx byte followed by another 4 bytes
(
On Mon, Sep 12, 2022 at 11:47:07AM +0700, John Naylor wrote:
> I don't think this clarifies anything, it's just a rephrasing.
>
> More broadly, I think the description of varlenas in this header is at
> a kind of "local maximum" -- minor adjustments are more likely to make
> it worse. To significa
On Thu, Aug 18, 2022 at 1:06 AM Aleksander Alekseev
wrote:
>
> Hi hackers,
>
> I noticed that the comments regarding bit layouts for varlena headers
> in postgres.h are somewhat misleading. For instance, when reading:
I agree it's confusing, but I don't think this patch is the right direction.
>
Hi John,
Thanks for the feedback.
> Maybe "00xx 4-byte length word (aligned)," is more clear about
> what is aligned. Also, adding all those xxx's obscures the point that
> we only need to examine one byte to figure out what to do next.
IMO "00xx 4-byte length word" is still confusing. O
On Tue, Sep 6, 2022 at 5:19 PM Aleksander Alekseev
wrote:
>
> Hi John,
>
> Thanks for the feedback.
>
> > Maybe "00xx 4-byte length word (aligned)," is more clear about
> > what is aligned. Also, adding all those xxx's obscures the point that
> > we only need to examine one byte to figure out
Hi John,
Many thanks for the feedback!
> Or put the now-standard 0b in front.
Good idea.
> I think the problem is ambiguity about what a "toast pointer" is. This
> comment:
>
> * struct varatt_external is a traditional "TOAST pointer", that is, the
Right. The comment for varatt_external says
On Sun, Sep 11, 2022 at 5:06 PM Aleksander Alekseev
wrote:
>
> Hi John,
>
> Many thanks for the feedback!
>
> > Or put the now-standard 0b in front.
>
> Good idea.
Now that I look at the results, though, it's distracting and not good
for readability. I'm not actually sure we need to do anything h
