Re: Improve WALRead() to suck data directly from WAL buffers when possible

Bharath Rupireddy <bharath.rupireddyforpostgres@gmail.com>

From: Bharath Rupireddy <bharath.rupireddyforpostgres@gmail.com>

To: Jeff Davis <pgsql@j-davis.com>

Cc: Andres Freund <andres@anarazel.de>, Alvaro Herrera <alvherre@alvh.no-ip.org>, Dilip Kumar <dilipbalaut@gmail.com>, Kyotaro Horiguchi <horikyota.ntt@gmail.com>, pgsql-hackers@lists.postgresql.org, Nathan Bossart <nathandbossart@gmail.com>, Masahiko Sawada <sawada.mshk@gmail.com>

Date: 2024-02-20T06:10:00Z

Lists: pgsql-hackers

Commits

Same data as JSON: GET /api/v1/messages/:b64id/commits the thread's linked commits as JSON, with link sources. API reference →

Add XLogCtl->logInsertResult
- f3ff7bf83bce 17.0 cited
Add assert to WALReadFromBuffers().
- 9ecbf54075a9 17.0 landed
Read WAL directly from WAL buffers.
- 91f2cae7a4e6 17.0 landed
Additional write barrier in AdvanceXLInsertBuffer().
- 766571be1659 17.0 landed
Use 64-bit atomics for xlblocks array elements.
- c3a8e2a7cb16 17.0 landed
Don't trust unvalidated xl_tot_len.
- bae868caf222 17.0 cited

Attachments

v25-0001-Add-check-in-WALReadFromBuffers-against-requeste.patch (application/octet-stream) patch v25-0001
v25-0002-Add-test-module-for-verifying-read-from-WAL-buff.patch (application/octet-stream) patch v25-0002
v25-0003-Use-WALReadFromBuffers-in-more-places.patch (application/octet-stream) patch v25-0003
v25-0004-Demonstrate-reading-unflushed-WAL-directly-from-.patch (application/octet-stream) patch v25-0004

On Sat, Feb 17, 2024 at 10:27 AM Bharath Rupireddy
<bharath.rupireddyforpostgres@gmail.com> wrote:
>
> On Fri, Feb 16, 2024 at 11:01 PM Jeff Davis <pgsql@j-davis.com> wrote:
> >
> > > Here, I'm with v23 patch set:
> >
> > Thank you, I'll look at these.
>
> Thanks. Here's the v24 patch set after rebasing.

Ran pgperltidy on the new TAP test file added. Please see the attached
v25 patch set.

--
Bharath Rupireddy
PostgreSQL Contributors Team
RDS Open Source Databases
Amazon Web Services: https://aws.amazon.com