Re: relfilenode statistics

Bertrand Drouvot <bertranddrouvot.pg@gmail.com>

From: Bertrand Drouvot <bertranddrouvot.pg@gmail.com>

To: Michael Paquier <michael@paquier.xyz>

Cc: pgsql-hackers@lists.postgresql.org

Date: 2024-08-05T05:28:22Z

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 more tests for relation statistics with rewrites
- b23fe993e136 19 (unreleased) landed

Attachments

v3-0001-Provide-relfilenode-statistics.patch (text/x-diff)

Hi,

On Thu, Jul 11, 2024 at 06:10:23AM +0000, Bertrand Drouvot wrote:
> Hi,
> 
> On Thu, Jul 11, 2024 at 01:58:19PM +0900, Michael Paquier wrote:
> > On Wed, Jul 10, 2024 at 01:38:06PM +0000, Bertrand Drouvot wrote:
> > > So, I think it makes sense to link the hashkey to all the RelFileLocator
> > > fields, means:
> > > 
> > > dboid (linked to RelFileLocator's dbOid)
> > > objoid (linked to RelFileLocator's spcOid)
> > > relfile (linked to RelFileLocator's relNumber)
> > 
> > Hmm.  How about using the table OID as objoid,
> 
> The issue is that we don't have the relation OID when writing buffers out (that's
> one of the reason explained in [1]).
> 
> [1]: https://www.postgresql.org/message-id/Zl2k8u4HDTUW6QlC%40ip-10-97-1-34.eu-west-3.compute.internal
> 
> Regards,
> 

Please find attached a mandatory rebase due to the recent changes around
statistics.

As mentioned up-thread:

The attached patch is not in a fully "polished" state yet: there is more places
we should add relfilenode counters, create more APIS to retrieve the relfilenode
stats....

It is in a state that can be used to discuss the approach it is implementing (as
we have done so far) before moving forward.

Regards,

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