Horton

Re: WIP patch for parallel pg_dump

Robert Haas <robertmhaas@gmail.com>

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From: Robert Haas <robertmhaas@gmail.com>
To: Andrew Dunstan <andrew@dunslane.net>
Cc: Tom Lane <tgl@sss.pgh.pa.us>, Greg Smith <greg@2ndquadrant.com>, Joachim Wieland <joe@mcknight.de>, Heikki Linnakangas <heikki.linnakangas@enterprisedb.com>, pgsql-hackers <pgsql-hackers@postgresql.org>
Date: 2010-12-06T02:27:58Z
Lists: pgsql-hackers 
On Sun, Dec 5, 2010 at 9:04 PM, Andrew Dunstan <andrew@dunslane.net> wrote:
> Why not just say give me the snapshot currently held by process nnnn?
>
> And please, not temp files if possible.

As far as I'm aware, the full snapshot doesn't normally exist in
shared memory, hence the need for publication of some sort.  We could
dedicate a shared memory region for publication but then you have to
decide how many slots to allocate, and any number you pick will be too
many for some people and not enough for others, not to mention that
shared memory is a fairly precious resource.

-- 
Robert Haas
EnterpriseDB: http://www.enterprisedb.com
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