public inbox for [email protected]  

help / color / mirror / Atom feed

From: Imran Zaheer <[email protected]>
To: Zsolt Parragi <[email protected]>
Cc: Hayato Kuroda (Fujitsu) <[email protected]>
Cc: pgsql-hackers <[email protected]>
Subject: Re: [WIP] Pipelined Recovery
Date: Wed, 18 Mar 2026 12:43:37 +0500
Message-ID: <CA+UBfamW6NuuMMQTDRPDQ0a9fWN_u2OvjEF98u3CfYKTBcOZMw@mail.gmail.com> (raw)
In-Reply-To: <CAN4CZFM7FV0VTNkujD=Mb7tNa+jkmEfnX7carvj95fY6Tp11FQ@mail.gmail.com>
References: <CA+UBfa=vDV8wbmAV0pgrx-FuJh+x8YOW23vJ90Jzr=14rV+9jA@mail.gmail.com>
	<OS9PR01MB12149A4E7927072A215AEED69F565A@OS9PR01MB12149.jpnprd01.prod.outlook.com>
	<CA+UBfakmkdtauuRsOVXFqhFVJt0nTdEadx94tJn+qG0Pe8Wjfw@mail.gmail.com>
	<CAN4CZFM7FV0VTNkujD=Mb7tNa+jkmEfnX7carvj95fY6Tp11FQ@mail.gmail.com>

Hi Zsolt.

Thanks alot for the review and pointing out the bugs. I have fixed the bugs
you mentioned in my new patch set. But
patchset mail is held for moderation for some reason.

>
>   if (reachedRecoveryTarget)
>   {
> + if (wal_pipeline_enabled)
> + WalPipeline_Stop();
>
> What if we didn't reach the recovery target, shouldn't we stop the
> pipelines then?
>

I have fixed the bugs shutdown logic.

As we already know we will exist the recovery redo loop in
`PerformWalRecovery()` only in two cases

1: Recovery target reached:
In this case consumers will call to stop the pipeline.

@@ -1807,6 +1931,9 @@ PerformWalRecovery(void)

  if (reachedRecoveryTarget)
  {
+ if (wal_pipeline_enabled)
+ WalPipeline_Stop();
+

2: Available pg_wal is consumed and now more wal to read.
In this case pipeline producers will send the shutdown msg to the consumer.
Consumer will
detect this message and then call ` WalPipeline_Stop`. This is the case
where we cannot read
more records and the while loop will break here.

+ if (decoded_record)
+ {
+ record = &decoded_record->header;
+ return record;
+ }
+ else
+ {
+ /*
+ * We will end up here only when pipeline couldn't read more
+ * records and have sent a shutdown msg. We will acknowldge this
+ * and will trigger request to stop the pipeline workers.
+ */
+ WalPipeline_Stop();
+ return NULL;
+ }


Hope this makes sense.

Once again thanks for reporting the bugs. You will receive the new patchset
mail soon once it is cleared from
the moderation.

Looking forward to your reviews, comments, etc.

Regards,
Imran Zaheer

view thread (9+ messages)  latest in thread

reply

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Reply to all the recipients using the --to and --cc options:
  reply via email

  To: [email protected]
  Cc: [email protected], [email protected], [email protected]
  Subject: Re: [WIP] Pipelined Recovery
  In-Reply-To: <CA+UBfamW6NuuMMQTDRPDQ0a9fWN_u2OvjEF98u3CfYKTBcOZMw@mail.gmail.com>

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

This inbox is served by agora; see mirroring instructions
for how to clone and mirror all data and code used for this inbox