Re: Vacuum: allow usage of more than 1GB of work mem - Mailing list pgsql-hackers

From Tom Lane
Subject Re: Vacuum: allow usage of more than 1GB of work mem
Date
Msg-id 16088.1473875862@sss.pgh.pa.us
Whole thread Raw
In response to Re: Vacuum: allow usage of more than 1GB of work mem  (Pavan Deolasee <pavan.deolasee@gmail.com>)
Responses Re: Vacuum: allow usage of more than 1GB of work mem  (Tomas Vondra <tomas.vondra@2ndquadrant.com>)
List pgsql-hackers
Pavan Deolasee <pavan.deolasee@gmail.com> writes:
> On Wed, Sep 14, 2016 at 10:53 PM, Alvaro Herrera <alvherre@2ndquadrant.com>
> wrote:
>> One thing not quite clear to me is how do we create the bitmap
>> representation starting from the array representation in midflight
>> without using twice as much memory transiently.  Are we going to write
>> the array to a temp file, free the array memory, then fill the bitmap by
>> reading the array from disk?

> We could do that.

People who are vacuuming because they are out of disk space will be very
very unhappy with that solution.
        regards, tom lane



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