Horton

Re: [HACKERS] CLUSTER command progress monitor

Peter Geoghegan <pg@bowt.ie>

View thread View on postgr.es
From: Peter Geoghegan <pg@bowt.ie>
To: Robert Haas <robertmhaas@gmail.com>
Cc: Michael Paquier <michael@paquier.xyz>, Masahiko Sawada <sawada.mshk@gmail.com>, Tatsuro Yamada <tatsuro.yamada.tf@nttcom.co.jp>, Alvaro Herrera <alvherre@2ndquadrant.com>, Rafia Sabih <rafia.pghackers@gmail.com>, Dmitry Dolgov <9erthalion6@gmail.com>, PostgreSQL-development <pgsql-hackers@postgresql.org>, Jeff Janes <jeff.janes@gmail.com>, Thomas Munro <thomas.munro@enterprisedb.com>, Michael Paquier <michael.paquier@gmail.com>, Peter Eisentraut <peter.eisentraut@2ndquadrant.com>
Date: 2019-09-09T22:13:10Z
Lists: pgsql-hackers 
On Fri, Sep 6, 2019 at 5:11 AM Robert Haas <robertmhaas@gmail.com> wrote:
> On Fri, Sep 6, 2019 at 1:44 AM Michael Paquier <michael@paquier.xyz> wrote:
> > I don't see exactly why we could not switch to a fixed number of
> > slots, say 8, with one code path to start a progress which adds an
> > extra report on the stack, one to remove one entry from the stack, and
> > a new one to reset the whole thing for a backend.  This would not need
> > much restructuration of course.
>
> You could do that, but I don't think it's probably that great of an
> idea.  Now you've built something which is significantly more complex
> than the original design of this feature, but still not good enough to
> report on the progress of a query tree.  I tend to think we should
> confine ourselves to the progress reporting that can reasonably be
> done within the current infrastructure until somebody invents a really
> general mechanism that can handle, essentially, an EXPLAIN-on-the-fly
> of a current query tree.

+1. Let's not complicate the progress reporting infrastructure for an
uncertain benefit.

CLUSTER/VACUUM FULL is fundamentally an awkward utility command to
target with progress reporting infrastructure. I think that it's okay
to redefine how progress reporting works with CLUSTER now, in order to
fix the REINDEX/CLUSTER state clobbering bug.

-- 
Peter Geoghegan

Commits

  1. Fix progress reporting of CLUSTER / VACUUM FULL

  2. Fix thinko when ending progress report for a backend

  3. Report progress of REINDEX operations

  4. Add progress reporting for CLUSTER and VACUUM FULL.

  5. Un-hide most cascaded-drop details in regression test results.

  6. Fix memory leak in printtup.c.

  7. Remove unused macro