On Mar 27, 2014, at 5:29 AM, Michael Paquier <michael.paqu...@gmail.com> wrote:
> On Thu, Mar 27, 2014 at 1:42 AM, Steven Schlansker <ste...@likeness.com> > wrote: >> >> On Mar 25, 2014, at 7:58 PM, Adrian Klaver <adrian.kla...@aklaver.com> wrote: >>>> >>> Yea, vacuum just marks space as available for reuse it does not actually >>> free space. >>> >> >> I even knew that. Funny what you'll forget when the system is down and >> you're in a panic. >> >> This is actually something that has bit me on more than one occasion -- if >> you accidentally temporarily use too much space, it is *very* hard to back >> out of the situation. It seems that the only way to actually release space >> to the system are VACUUM FULL, CLUSTER, or to DROP objects. None of these >> can be executed without severe disruption to a running database. A cluster >> operation on any of our tables that are large enough to matter can easily >> run through the night. > Yep, depending on your application needs you could actually avoid any > periodic VACUUM FULL-like operations that need an exclusive lock on > the objects it is cleaning by making autovacuum more aggressive. This > makes your house cleaner by dropping the garbage at a higher > frequency. Yes, although this will not save you in a couple of notable cases. We have run into this at least by: * Accidentally leaving transactions open for days * Runaway process inserting data until the disk fills So yes we should autovacuum more, but it is not a total solution. -- Sent via pgsql-general mailing list (pgsql-general@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-general
