RE: sequencesync worker race with REFRESH SEQUENCES

From: "Hayato Kuroda (Fujitsu)" <kuroda(dot)hayato(at)fujitsu(dot)com>
To: 'vignesh C' <vignesh21(at)gmail(dot)com>
Cc: "amit(dot)kapila16(at)gmail(dot)com" <amit(dot)kapila16(at)gmail(dot)com>, "pgsql-hackers(at)postgresql(dot)org" <pgsql-hackers(at)postgresql(dot)org>, Noah Misch <noah(at)leadboat(dot)com>
Subject: RE: sequencesync worker race with REFRESH SEQUENCES
Date: 2026-07-24 05:19:10
Message-ID: OS9PR01MB1214922AE07732C4592D1AB5EF5CF2@OS9PR01MB12149.jpnprd01.prod.outlook.com
Views: Whole Thread | Raw Message | Download mbox | Resend email
Thread:
Lists: pgsql-hackers

Dear Vignesh,

> a) Finding 9: A running sequence synchronization worker continues
> processing after ALTER SUBSCRIPTION ... DISABLE. In this case the
> leader apply worker only terminated its parallel apply workers on
> detach, so a running sequencesync worker could outlive a DISABLE.
> logicalrep_worker_detach() now also stops the sequencesync worker.

Hmm, but tablesync workers, which can connect to the publisher by itself are not
terminated by the function. IIUC, tablesync workers can read the subscription
catalog and recognize the catalog. I feel we should follow that approach.

Note: I cannot find the place sequencesync worker calls maybe_reread_subscription().
It might mean that the worker cannot recognize alternations of the subscription.

Best regards,
Hayato Kuroda
FUJITSU LIMITED

In response to

Browse pgsql-hackers by date

  From Date Subject
Next Message Xuneng Zhou 2026-07-24 05:40:16 Re: BUG: ReadStream look-ahead exhausts local buffers when effective_io_concurrency>=64
Previous Message Henson Choi 2026-07-24 05:11:07 Re: [PATCH] Fix quotation logic for unreserved keywords in window specifications