Regardign RecentFlushPtr in WalSndWaitForWal()

From: shveta malik <shveta(dot)malik(at)gmail(dot)com>
To: pgsql-hackers <pgsql-hackers(at)postgresql(dot)org>
Cc: Robert Haas <robertmhaas(at)gmail(dot)com>, Amit Kapila <amit(dot)kapila16(at)gmail(dot)com>, shveta malik <shveta(dot)malik(at)gmail(dot)com>
Subject: Regardign RecentFlushPtr in WalSndWaitForWal()
Date: 2024-02-26 11:46:39
Message-ID: CAJpy0uBSCQz1yMD-WiEthzEe23dti2-Kr_pitVb7vAPFbFKm=A@mail.gmail.com
Views: Raw Message | Whole Thread | Download mbox | Resend email
Thread:
Lists: pgsql-hackers

Hi hackers,

I would like to understand why we have code [1] that retrieves
RecentFlushPtr in WalSndWaitForWal() outside of the loop. We utilize
RecentFlushPtr later within the loop, but prior to that, we already
have [2]. Wouldn't [2] alone be sufficient?

Just to check the impact, I ran 'make check-world' after removing [1],
and did not see any issue exposed by the test at-least.

Any thoughts?

[1]:
/* Get a more recent flush pointer. */
if (!RecoveryInProgress())
RecentFlushPtr = GetFlushRecPtr(NULL);
else
RecentFlushPtr = GetXLogReplayRecPtr(NULL);

[2]:
/* Update our idea of the currently flushed position. */
else if (!RecoveryInProgress())
RecentFlushPtr = GetFlushRecPtr(NULL);
else
RecentFlushPtr = GetXLogReplayRecPtr(NULL);

thanks
Shveta

Responses

Browse pgsql-hackers by date

  From Date Subject
Next Message Amit Kapila 2024-02-26 11:48:25 Re: Synchronizing slots from primary to standby
Previous Message Xing Guo 2024-02-26 11:42:18 Re: Control your disk usage in PG: Introduction to Disk Quota Extension