| From: | Simon Riggs <simon(at)2ndquadrant(dot)com> |
|---|---|
| To: | Bruce Momjian <bruce(at)momjian(dot)us> |
| Cc: | Pavan Deolasee <pavan(dot)deolasee(at)gmail(dot)com>, pgsql-hackers <pgsql-hackers(at)postgresql(dot)org> |
| Subject: | Re: Heap WARM Tuples - Design Draft |
| Date: | 2016-08-04 17:16:02 |
| Message-ID: | CANP8+jJe97JEZ9Na_b0Q1nNSV_jNV27SwP-2mH03Dy3ersOVtQ@mail.gmail.com |
| Views: | Raw Message | Whole Thread | Download mbox | Resend email |
| Thread: | |
| Lists: | pgsql-hackers |
On 4 August 2016 at 18:05, Bruce Momjian <bruce(at)momjian(dot)us> wrote:
>> Approach 2 seems more reasonable and simple.
>>
>> There are only 2 bits for lp_flags and all combinations are already used. But
>> for LP_REDIRECT root line pointer, we could use the lp_len field to store this
>> special flag, which is not used for LP_REDIRECT line pointers. So we are able
>> to mark the root line pointer.
>
> Uh, as I understand it, we only use LP_REDIRECT when we have _removed_
> the tuple that the ctid was pointing to, but it seems you would need to
> set HEAP_RECHECK_REQUIRED earlier than that.
Hmm. Mostly there will be one, so this is just for the first update
after any VACUUM.
Adding a new linepointer just to hold this seems kludgy and could mean
we run out of linepointers.
--
Simon Riggs http://www.2ndQuadrant.com/
PostgreSQL Development, 24x7 Support, Remote DBA, Training & Services
| From | Date | Subject | |
|---|---|---|---|
| Next Message | Bruce Momjian | 2016-08-04 17:16:35 | Re: Heap WARM Tuples - Design Draft |
| Previous Message | Claudio Freire | 2016-08-04 17:14:37 | Re: Heap WARM Tuples - Design Draft |