From: Tom Lane <tgl@sss.pgh.pa.us>
To: Thomas Munro <thomas.munro@enterprisedb.com>
cc: Pg Hackers <pgsql-hackers@postgresql.org>
Subject: Re: DSM segment handle generation in background workers
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Comments: In-reply-to Thomas Munro <thomas.munro@enterprisedb.com>
	message dated "Tue, 09 Oct 2018 13:38:54 +1300"
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Date: Mon, 08 Oct 2018 20:53:29 -0400
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Thomas Munro <thomas.munro@enterprisedb.com> writes:
> On Mon, Oct 8, 2018 at 1:17 AM Thomas Munro
> <thomas.munro@enterprisedb.com> wrote:
>> That's because the bgworker startup path doesn't contain a call to
>> srandom(...distinguishing stuff...), unlike BackendRun().  I suppose
>> do_start_bgworker() could gain a similar call... or perhaps that call
>> should be moved into InitPostmasterChild().  If we put it in there
>> right after MyStartTime is assigned a new value, we could use the same
>> incantation that PostmasterMain() uses.

> Maybe something like this?

I think the bit with

#ifndef HAVE_STRONG_RANDOM
 	random_seed = 0;
 	random_start_time.tv_usec = 0;
#endif

should also be done in every postmaster child, no?  If we want to hide the
postmaster's state from child processes, we ought to hide it from all.

			regards, tom lane