Re: Differential Backups - Mailing list pgsql-general

From Paul Tomblin
Subject Re: Differential Backups
Date
Msg-id 20011030082115.A19947@allhats.xcski.com
Whole thread Raw
In response to Re: Differential Backups  (Alvaro Herrera <alvherre@atentus.com>)
List pgsql-general
Quoting Alvaro Herrera (alvherre@atentus.com):
> On Mon, 29 Oct 2001, Paul Tomblin wrote:
> > Quoting Alvaro Herrera (alvherre@atentus.com):
> > > > Interesting idea.  The one thing I might worry about is that 'diff'
> > > > might (I'm not familiar with its algorithm) eat a great deal of memory
> > > > if the dumps you're comparing are very large and significantly
> > > > different.
> > >
> > > GNU diff reads in memory both files. You sure need lots to compare
> > > medium sized databases, and I don't think this method will work on big
> > > ones.
> >
> > Doesn't GNU diff have the "-h" option?
>
> No, at least in my version of it (2.7, which appears to be the latest in
> my local mirror of GNU). What's that supposed to do? In fact, the help
> text says
>
>        -h     This  option currently has no effect; it is present
>               for Unix compatibility.

The option I'm thinking of might be "-H".  The old man pages used to say
it stood for "half hearted", optimized for large files with few
differences.


--
Paul Tomblin <ptomblin@xcski.com>, not speaking for anybody
God does not play dice with the Universe.    -- Albert Einstein.

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