| From: | Andres Freund <andres(at)2ndquadrant(dot)com> |
|---|---|
| To: | Simon Riggs <simon(at)2ndQuadrant(dot)com> |
| Cc: | Peter Geoghegan <pg(at)heroku(dot)com>, Noah Misch <noah(at)leadboat(dot)com>, pgsql-hackers <pgsql-hackers(at)postgresql(dot)org> |
| Subject: | Re: ALTER TABLE lock strength reduction patch is unsafe |
| Date: | 2014-02-26 13:38:43 |
| Message-ID: | 20140226133843.GY6718@awork2.anarazel.de |
| Views: | Whole Thread | Raw Message | Download mbox | Resend email |
| Thread: | |
| Lists: | pgsql-hackers |
Hi,
On 2014-02-26 07:32:45 +0000, Simon Riggs wrote:
> > * This definitely should include isolationtester tests actually
> > performing concurrent ALTER TABLEs. All that's currently there is
> > tests that the locklevel isn't too high, but not that it actually works.
>
> There is no concurrent behaviour here, hence no code that would be
> exercised by concurrent tests.
Huh? There's most definitely new concurrent behaviour. Previously no
other backends could have a relation open (and locked) while it got
altered (which then sends out relcache invalidations). That's something
that should be tested.
> > * Why does ChangeOwner need AEL?
>
> Ownership affects privileges, which includes SELECTs, hence AEL.
So?
Greetings,
Andres Freund
--
Andres Freund http://www.2ndQuadrant.com/
PostgreSQL Development, 24x7 Support, Training & Services
| From | Date | Subject | |
|---|---|---|---|
| Next Message | Thom Brown | 2014-02-26 13:55:39 | Re: pgsql: Allow time delayed standbys and recovery |
| Previous Message | Simon Riggs | 2014-02-26 13:32:25 | Re: pgsql: Allow time delayed standbys and recovery |