| From: | Robert Haas <robertmhaas(at)gmail(dot)com> |
|---|---|
| To: | Andres Freund <andres(at)anarazel(dot)de> |
| Cc: | Amit Kapila <amit(dot)kapila16(at)gmail(dot)com>, Dilip Kumar <dilipbalaut(at)gmail(dot)com>, Thomas Munro <thomas(dot)munro(at)gmail(dot)com>, Dmitry Dolgov <9erthalion6(at)gmail(dot)com>, Kuntal Ghosh <kuntalghosh(dot)2007(at)gmail(dot)com>, Pg Hackers <pgsql-hackers(at)postgresql(dot)org> |
| Subject: | Re: POC: Cleaning up orphaned files using undo logs |
| Date: | 2019-08-20 14:34:24 |
| Message-ID: | CA+TgmobyZcDcV0M4zyDey4rOdyDwQA_G8bhLKM+hdx51Vz+aiA@mail.gmail.com |
| Views: | Raw Message | Whole Thread | Download mbox | Resend email |
| Thread: | |
| Lists: | pgsql-hackers |
On Mon, Aug 19, 2019 at 5:16 PM Andres Freund <andres(at)anarazel(dot)de> wrote:
> Well, my main point, which so far has largely been ignored, was that we
> may not acquire page locks when we still need to search for victim
> buffers later. If we don't need to lock the pages up-front, but only do
> so once we're actually copying the records into the undo pages, then we
> don't a separate phase to acquire the locks. We can still hold all of
> the page locks at the same time, as long as we just acquire them at the
> later stage.
+1 for that approach. I am in complete agreement.
> My secondary point was that *none* of this actually is
> documented, even if it's entirely unobvious to the reader that the
> relevant code can only run during WAL insertion, due to being pretty far
> removed from that.
+1 also for properly documenting stuff.
--
Robert Haas
EnterpriseDB: http://www.enterprisedb.com
The Enterprise PostgreSQL Company
| From | Date | Subject | |
|---|---|---|---|
| Next Message | Rafia Sabih | 2019-08-20 14:37:51 | Improve default partition |
| Previous Message | Robert Haas | 2019-08-20 14:33:12 | Re: POC: Cleaning up orphaned files using undo logs |