Обсуждение: docs/9.1/static/kernel-resources.html needs updating for NetBSD

Hello

The NetBSD paragraph about setting the amount of shared memory for
NetBSD in
http://www.postgresql.org/docs/9.1/static/kernel-resources.html is outdated.

Since NetBSD 5.0 the shared memory size settings can be changed via the
sysctl interface. For example, to allow 16 MB:
# sysctl -w kern.ipc.shmmax=16777216
In addition these settings can be preserved between reboots in the file
/etc/sysctl.conf.


This part is still valid
"
You might also want to configure your kernel to lock shared memory into
RAM and prevent it from being paged out to swap. This can be
accomplished using the sysctl setting kern.ipc.shm_use_phys.
"

Manu

Emmanuel Kasper <emmanuel@libera.cc> writes:
> The NetBSD paragraph about setting the amount of shared memory for
> NetBSD in
> http://www.postgresql.org/docs/9.1/static/kernel-resources.html is outdated.

> Since NetBSD 5.0 the shared memory size settings can be changed via the
> sysctl interface.

Thanks for the info.  I gather from
http://www.daemon-systems.org/man/sysctl.7.html
that it's still necessary to make sure that SysV IPC code is compiled
into the kernel at all --- should we retain the first sentence that
mentions that, or do you think it's unnecessary?

            regards, tom lane

Le 30/11/2011 16:31, Tom Lane a écrit :
> Emmanuel Kasper <emmanuel@libera.cc> writes:
>> The NetBSD paragraph about setting the amount of shared memory for
>> NetBSD in
>> http://www.postgresql.org/docs/9.1/static/kernel-resources.html is outdated.
>
>> Since NetBSD 5.0 the shared memory size settings can be changed via the
>> sysctl interface.
>
> Thanks for the info.  I gather from
> http://www.daemon-systems.org/man/sysctl.7.html
> that it's still necessary to make sure that SysV IPC code is compiled
> into the kernel at all --- should we retain the first sentence that
> mentions that, or do you think it's unnecessary?
>
>             regards, tom lane
>

I have grep'ed the NetBSD source tree, and the System V compatible IPC
subsystem is compiled by default on nearly all Tier One ports, the
exceptions being uncommon embedded board where I guess the port user is
knowing what he is doing.
So I think it is safe to drop that sentence.

PS: you can use the official man.netbsd.org if you're looking for NetBSD
man pages


find amd64 evbarm evbmips evbppc hpcarm i386 sparc64 xen | xargs grep
"^options.*SYSVSHM"

amd64/conf/XEN3_DOMU:options     SYSVSHM        # System V-like memory sharing
amd64/conf/GENERIC:options     SYSVSHM        # System V-like memory sharing
amd64/conf/XEN3_DOM0:options     SYSVSHM        # System V-like memory sharing
evbarm/conf/ARMADILLO9:options     SYSVSHM        # System V-like memory sharing
evbarm/conf/IXDP425:options     SYSVSHM        # System V-like memory sharing
evbarm/conf/MPCSA_GENERIC:options     SYSVSHM        # System V-like memory sharing
evbarm/conf/VIPER:options     SYSVSHM        # System V-like memory sharing
evbarm/conf/TISDP2430:options     SYSVSHM        # System V-like memory sharing
evbarm/conf/HDL_G:options     SYSVSHM        # System V-like memory sharing
evbarm/conf/ADI_BRH:options     SYSVSHM        # System V-like memory sharing
evbarm/conf/TS7200:options     SYSVSHM        # System V-like memory sharing
evbarm/conf/IQ80321:options     SYSVSHM        # System V-like memory sharing
evbarm/conf/TEAMASA_NPWR:options     SYSVSHM        # System V-like memory sharing
evbarm/conf/OSK5912:options     SYSVSHM        # System V-like memory sharing
evbarm/conf/IQ80310:options     SYSVSHM        # System V-like memory sharing
evbarm/conf/BEAGLEBOARD:options     SYSVSHM        # System V-like memory sharing
evbarm/conf/GEMINI:options     SYSVSHM        # System V-like memory sharing
evbarm/conf/CP3100:options     SYSVSHM        # System V-like memory sharing
evbarm/conf/IXM1200:options     SYSVSHM        # System V-like memory sharing
evbarm/conf/TISDP2420:options     SYSVSHM        # System V-like memory sharing
evbarm/conf/TEAMASA_NPWR_FC:options     SYSVSHM        # System V-like memory sharing
evbarm/conf/IQ31244:options     SYSVSHM        # System V-like memory sharing
evbarm/conf/IMX31LITE:options     SYSVSHM        # System V-like memory sharing
evbarm/conf/ZAO425:options     SYSVSHM        # System V-like memory sharing
evbarm/conf/NAPPI:options     SYSVSHM        # System V-like memory sharing
evbarm/conf/SMDK2410:options     SYSVSHM        # System V-like memory sharing
evbmips/conf/ALCHEMY:options     SYSVSHM        # System V shared memory
evbmips/conf/MALTA:options     SYSVSHM        # System V shared memory
evbppc/conf/OPENBLOCKS200:options     SYSVSHM        # System V shared memory
evbppc/conf/PMPPC:options     SYSVSHM        # System V shared memory
evbppc/conf/EXPLORA451:options     SYSVSHM        # System V-like memory sharing
evbppc/conf/EV64260:options     SYSVSHM        # System V shared memory
evbppc/conf/OPENBLOCKS266:options     SYSVSHM            # System V shared memory
evbppc/conf/WALNUT:options     SYSVSHM        # System V shared memory
hpcarm/conf/JORNADA820:options     SYSVSHM        # System V-like memory sharing
hpcarm/conf/JORNADA720:options     SYSVSHM        # System V-like memory sharing
hpcarm/conf/IPAQ:options     SYSVSHM        # System V-like memory sharing
i386/conf/NET4501:options     SYSVSHM        # System V-like memory sharing
i386/conf/XEN2_DOM0:options     SYSVSHM        # System V-like memory sharing
i386/conf/KVM:options     SYSVSHM        # System V-like memory sharing
i386/conf/ALL:options     SYSVSHM        # System V-like memory sharing
i386/conf/GENERIC:options     SYSVSHM        # System V-like memory sharing
i386/conf/GENERIC_PS2TINY:options     SYSVSHM        # System V-like memory sharing
i386/conf/XEN2_DOMU:options     SYSVSHM        # System V-like memory sharing
sparc64/conf/NONPLUS64:options     SYSVSHM        # System V shared memory
sparc64/conf/GENERIC:options     SYSVSHM        # System V shared memory

Emmanuel Kasper <emmanuel@libera.cc> writes:
> Le 30/11/2011 16:31, Tom Lane a �crit :
>> Thanks for the info.  I gather from
>> http://www.daemon-systems.org/man/sysctl.7.html
>> that it's still necessary to make sure that SysV IPC code is compiled
>> into the kernel at all --- should we retain the first sentence that
>> mentions that, or do you think it's unnecessary?

> I have grep'ed the NetBSD source tree, and the System V compatible IPC
> subsystem is compiled by default on nearly all Tier One ports, the
> exceptions being uncommon embedded board where I guess the port user is
> knowing what he is doing.
> So I think it is safe to drop that sentence.

OK, documentation updated.  Thanks for the info!

            regards, tom lane