From: Jan Wieck <JanWieck@Yahoo.com>
To: Jens Lechtenboerger <lechten@wi.uni-muenster.de>
Cc: Greg Stark <gsstark@mit.edu>
Cc: pgsql-interfaces@postgresql.org
Subject: Re: Lost updates vs resumable connections/transactions
Date: Fri, 17 Dec 2004 11:17:37 -0500
Message-ID: <41C306A1.1070807@Yahoo.com> (raw)
In-Reply-To: <m21xdpkpgy.fsf@pcwi4002.uni-muenster.de>
References: <Pine.A41.4.58.0412091641060.68588@zivunix.uni-muenster.de>
<41C06961.8020406@Yahoo.com>
<87is73qrde.fsf@stark.xeocode.com>
<m2y8fyl58u.fsf@pcwi4002.uni-muenster.de>
<41C1CE7A.10405@Yahoo.com>
<m21xdpkpgy.fsf@pcwi4002.uni-muenster.de>
On 12/17/2004 8:45 AM, Jens Lechtenboerger wrote:
> [...]
> When the connection is resumed, the postmaster creates a new socket
> with the (new) Apache process (just as you described above), gets
> the ID, informs the backend, and passes the new socket with
> sendmsg(2) to the backend which gets it with recvmsg(2). (I have
> never passed sockets like this; I just read that it should work.)
> Now the backend can continue the existing transaction with the new
> Apache process.
>
> Or not?
Yes, that would work ... on some but not all Unix derivates ... what
about those where it does not? I know that Windows has a similar
functionality available, but that would AFAIK require to use windows
messages, which in turn requires to have a window handle for each and
every backend, a rather dramatic change.
The PostgreSQL team members (me included) are big fans of portability.
Introducing code that solves a problem for one specific web server, in
the special case of a small number of application users, in a non
portable way for only a couple operating systems and where the resulting
functional difference is visible to the database client ... I don't
think this idea has much of a chance to make it into the source tree.
Jan
--
#======================================================================#
# It's easier to get forgiveness for being wrong than for being right. #
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#================================================== JanWieck@Yahoo.com #
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To: pgsql-interfaces@postgresql.org
Cc: JanWieck@Yahoo.com, lechten@wi.uni-muenster.de, gsstark@mit.edu
Subject: Re: Lost updates vs resumable connections/transactions
In-Reply-To: <41C306A1.1070807@Yahoo.com>
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