RE: [HACKERS] Linux: semaphores: How?

From: "Daryl W(dot) Dunbar" <daryl(at)www(dot)com>
To: <phd2(at)earthling(dot)net>, "Terry Mackintosh" <terry(at)terrym(dot)com>
Cc: "PostgreSQL-development" <hackers(at)postgreSQL(dot)org>
Subject: RE: [HACKERS] Linux: semaphores: How?
Date: 1999-02-25 23:16:45
Message-ID: 011301be6114$e9593390$1445e59b@ddunbar.eni.net
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The defaults for RH5.2 (from /usr/src/linux/include/linux/sem.h:

#define SEMMNI 128 /* ? max # of semaphore identifiers
*/
#define SEMMSL 32 /* <= 512 max num of semaphores per
id */
#define SEMMNS (SEMMNI*SEMMSL) /* ? max # of semaphores in system
*/
#define SEMOPM 32 /* ~ 100 max num of ops per semop
call */
#define SEMVMX 32767 /* semaphore maximum value */

Which means the default max semaphores is 128*32 = 4096, I don't
think you'll have a problem. :)

DwD

> -----Original Message-----
> From: owner-pgsql-hackers(at)postgreSQL(dot)org
> [mailto:owner-pgsql-hackers(at)postgreSQL(dot)org]On Behalf Of
> Oleg Broytmann
> Sent: Thursday, February 25, 1999 12:42 PM
> To: Terry Mackintosh
> Cc: PostgreSQL-development
> Subject: Re: [HACKERS] Linux: semaphores: How?
>
>
> Hi!
>
> On Thu, 25 Feb 1999, Terry Mackintosh wrote:
> > I'm now building up a new server, Red Hat 5.2 with
> updates and the new
> > 2.2.2 kernel.
> >
> > I may have missed it, but do not recall seeing any
> thing about semaphores
> > in the "make menuconfig", is it call some thing else?
> or is it N/A for
> > Linux? or did I just not see it?
>
> It is "System V IPC".
>
> Oleg.
> ----
> Oleg Broytmann National Research Surgery Centre
> http://sun.med.ru/~phd/
> Programmers don't die,
> they just GOSUB without RETURN.
>
>

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