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From: Tom Lane <tgl@sss.pgh.pa.us>
To: Scott Ribe <scott_ribe@elevated-dev.com>
cc: pgsql-admin <pgsql-admin@postgresql.org>
Subject: Re: shm
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Comments: In-reply-to Scott Ribe <scott_ribe@elevated-dev.com>
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Scott Ribe <scott_ribe@elevated-dev.com> writes:
> What is POSIX shared memory used for anymore?

We still allocate a small shm block as a means of counting live backends
(since the SysV spec includes an "nattch" count but mmap'd segments do
not provide that info).  Should only be ~50 bytes though.

			regards, tom lane