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Subject: Re: Back-patch use of unnamed POSIX semaphores for Linux?
To: Tom Lane <tgl@sss.pgh.pa.us>, pgsql-hackers@postgreSQL.org
References: <32387.1481079186@sss.pgh.pa.us>
From: Peter Eisentraut <peter.eisentraut@2ndquadrant.com>
Organization: 2ndQuadrant
Message-ID: <722c489e-810a-be9c-f005-3b6bdcb4c59f@2ndquadrant.com>
Date: Wed, 7 Dec 2016 08:54:17 -0500
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On 12/6/16 9:53 PM, Tom Lane wrote:
> I think we should give serious consideration to back-patching commit
> ecb0d20a9, which changed the default semaphore type to unnamed-POSIX
> on Linux.

Even with that change, dynamic shared memory is still vulnerable to be
removed.  So backpatching the semaphore change wouldn't achieve any new
level of safety for users so that we could tell them, "you're good now".

-- 
Peter Eisentraut              http://www.2ndQuadrant.com/
PostgreSQL Development, 24x7 Support, Remote DBA, Training & Services


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