I have Informix dynamic server 9.20.UC1 installed on Sun Solaris machine.
The shmmin setting in /etc/system is set to 64. Sun recommends to set it to
1.
Can anyone tell me if it is ok to change the value to 1?
Any addintional information about it is welcome.

AFAIR the shmmin of 1 is required for powerd, if you are not using
power management then leave it at 64

jjjj wrote:
>
> I have Informix dynamic server 9.20.UC1 installed on Sun Solaris machine.
> The shmmin setting in /etc/system is set to 64. Sun recommends to set it to
> 1.
> Can anyone tell me if it is ok to change the value to 1?
> Any addintional information about it is welcome.

--
Paul Watson #
Oninit Ltd # Growing old is mandatory
Tel: +44 1436 672201 # Growing up is optional
Fax: +44 1436 678693 #
Mob: +44 7818 003457 #
www.oninit.com #

Paul Watson wrote:

> AFAIR the shmmin of 1 is required for powerd, if you are not using
> power management then leave it at 64


I agree with the first half - powerd is the primary system user. On
Solaris 7, I set it to 16 because powerd used a somewhat bigger number
(28 bytes?). On Solaris 8, powerd only uses 4 bytes. Informix
doesn't care what the value is as long as it is small enough to permit
the smallest segment IDS wants to allocate - which would probably be
in the 1KB range.

I disagree with the conclusion - if Sun recommends 1, use 1. It's
their o/s. Setting it to 1 won't harm Informix - and not setting it
to 1 might harm your system.

> jjjj wrote:
>> I have Informix dynamic server 9.20.UC1 installed on Sun Solaris
>> machine. The shmmin setting in /etc/system is set to 64. Sun
>> recommends to set it to 1. Can anyone tell me if it is ok to
>> change the value to 1? Any addintional information about it is
>> welcome.


--
Jonathan Leffler #include <disclaimer.h>
Email: jleffler@earthlink.net, jleffler@us.ibm.com
Guardian of DBD::Informix v2003.04 -- http://dbi.perl.org/

I've set to 64 for years without any problems. If Sun recommend 1 it
then it seems odd that Informix recommend 64 in the release notes

Jonathan Leffler wrote:
>
> Paul Watson wrote:
>
> > AFAIR the shmmin of 1 is required for powerd, if you are not using
> > power management then leave it at 64
>
> I agree with the first half - powerd is the primary system user. On
> Solaris 7, I set it to 16 because powerd used a somewhat bigger number
> (28 bytes?). On Solaris 8, powerd only uses 4 bytes. Informix
> doesn't care what the value is as long as it is small enough to permit
> the smallest segment IDS wants to allocate - which would probably be
> in the 1KB range.
>
> I disagree with the conclusion - if Sun recommends 1, use 1. It's
> their o/s. Setting it to 1 won't harm Informix - and not setting it
> to 1 might harm your system.
>
> > jjjj wrote:
> >> I have Informix dynamic server 9.20.UC1 installed on Sun Solaris
> >> machine. The shmmin setting in /etc/system is set to 64. Sun
> >> recommends to set it to 1. Can anyone tell me if it is ok to
> >> change the value to 1? Any addintional information about it is
> >> welcome.
>
> --
> Jonathan Leffler #include <disclaimer.h>
> Email: jleffler@earthlink.net, jleffler@us.ibm.com
> Guardian of DBD::Informix v2003.04 -- http://dbi.perl.org/

--
Paul Watson #
Oninit Ltd # Growing old is mandatory
Tel: +44 1436 672201 # Growing up is optional
Fax: +44 1436 678693 #
Mob: +44 7818 003457 #
www.oninit.com #

powerd (1M) is the power management daemon, you get an EINVAL if
you attempt to start it with shmmin over 68. There is no need
for powerd to running unless you want the machine to shutdown
automatically due to idle time or low battery etc.

I believe powerd became default in 2.4 but that was a while back. But
I suspect that was when the /etc/system recommendations from Informix
were set as they still mentions enable_sm_va

Jonathan Leffler wrote:
>
> Paul Watson wrote:
>
> > AFAIR the shmmin of 1 is required for powerd, if you are not using
> > power management then leave it at 64
>
> I agree with the first half - powerd is the primary system user. On
> Solaris 7, I set it to 16 because powerd used a somewhat bigger number
> (28 bytes?). On Solaris 8, powerd only uses 4 bytes. Informix
> doesn't care what the value is as long as it is small enough to permit
> the smallest segment IDS wants to allocate - which would probably be
> in the 1KB range.
>
> I disagree with the conclusion - if Sun recommends 1, use 1. It's
> their o/s. Setting it to 1 won't harm Informix - and not setting it
> to 1 might harm your system.
>
> > jjjj wrote:
> >> I have Informix dynamic server 9.20.UC1 installed on Sun Solaris
> >> machine. The shmmin setting in /etc/system is set to 64. Sun
> >> recommends to set it to 1. Can anyone tell me if it is ok to
> >> change the value to 1? Any addintional information about it is
> >> welcome.
>
> --
> Jonathan Leffler #include <disclaimer.h>
> Email: jleffler@earthlink.net, jleffler@us.ibm.com
> Guardian of DBD::Informix v2003.04 -- http://dbi.perl.org/

--
Paul Watson #
Oninit Ltd # Growing old is mandatory
Tel: +44 1436 672201 # Growing up is optional
Fax: +44 1436 678693 #
Mob: +44 7818 003457 #
www.oninit.com #

"Paul Watson" <paul@oninit.com> wrote in message
news:3FB39F92.6E341A38@oninit.com...
> I've set to 64 for years without any problems. If Sun recommend 1 it
> then it seems odd that Informix recommend 64 in the release notes
>

Last time I looked more closely at the release notes- informix do not
recommend 64. 64
is what was used on the machine that Informix did their testing!!

Use 1 as their is other software (Sonnet for printing?) which needs small
shared memory
segments.

Can someone get Informix to change their release notes? And get rid of
enable_sm_wa
as well. Surely Informix no longer use Solaris 2.4 for porting and it is
not a supported
platform any more?



> Jonathan Leffler wrote:
> >
> > Paul Watson wrote:
> >
> > > AFAIR the shmmin of 1 is required for powerd, if you are not using
> > > power management then leave it at 64
> >
> > I agree with the first half - powerd is the primary system user. On
> > Solaris 7, I set it to 16 because powerd used a somewhat bigger number
> > (28 bytes?). On Solaris 8, powerd only uses 4 bytes. Informix
> > doesn't care what the value is as long as it is small enough to permit
> > the smallest segment IDS wants to allocate - which would probably be
> > in the 1KB range.
> >
> > I disagree with the conclusion - if Sun recommends 1, use 1. It's
> > their o/s. Setting it to 1 won't harm Informix - and not setting it
> > to 1 might harm your system.
> >
> > > jjjj wrote:
> > >> I have Informix dynamic server 9.20.UC1 installed on Sun Solaris
> > >> machine. The shmmin setting in /etc/system is set to 64. Sun
> > >> recommends to set it to 1. Can anyone tell me if it is ok to
> > >> change the value to 1? Any addintional information about it is
> > >> welcome.
> >
> > --
> > Jonathan Leffler #include <disclaimer.h>
> > Email: jleffler@earthlink.net, jleffler@us.ibm.com
> > Guardian of DBD::Informix v2003.04 -- http://dbi.perl.org/
>
> --
> Paul Watson #
> Oninit Ltd # Growing old is mandatory
> Tel: +44 1436 672201 # Growing up is optional
> Fax: +44 1436 678693 #
> Mob: +44 7818 003457 #
> www.oninit.com #

Paul Watson wrote:

> I've set to 64 for years without any problems. If Sun recommend 1 it
> then it seems odd that Informix recommend 64 in the release notes

Why? We recommended enable_sm_wa for aeons too. It enabled a shared
memory workaround in Solaris 2.4; not relevant in Solaris 2.5 or
later. I think we got rid of it in the 9.40 release notes (or my
comment saying it should be removed got ignored again).

The rules should be roughly:

shmmin <= MIN(min value for all things that need it set)
shmmax >= MAX(max value for all things that need it set)

> Jonathan Leffler wrote:
>>Paul Watson wrote:
>>>AFAIR the shmmin of 1 is required for powerd, if you are not using
>>>power management then leave it at 64
>>
>>I agree with the first half - powerd is the primary system user. On
>>Solaris 7, I set it to 16 because powerd used a somewhat bigger number
>>(28 bytes?). On Solaris 8, powerd only uses 4 bytes. Informix
>>doesn't care what the value is as long as it is small enough to permit
>>the smallest segment IDS wants to allocate - which would probably be
>>in the 1KB range.
>>
>>I disagree with the conclusion - if Sun recommends 1, use 1. It's
>>their o/s. Setting it to 1 won't harm Informix - and not setting it
>>to 1 might harm your system.
>>
>>>jjjj wrote:
>>>>I have Informix dynamic server 9.20.UC1 installed on Sun Solaris
>>>>machine. The shmmin setting in /etc/system is set to 64. Sun
>>>>recommends to set it to 1. Can anyone tell me if it is ok to
>>>>change the value to 1? Any addintional information about it is
>>>>welcome.



--
Jonathan Leffler #include <disclaimer.h>
Email: jleffler@earthlink.net, jleffler@us.ibm.com
Guardian of DBD::Informix v2003.04 -- http://dbi.perl.org/

David Williams wrote:
>
> "Paul Watson" <paul@oninit.com> wrote in message
> news:3FB39F92.6E341A38@oninit.com...
> > I've set to 64 for years without any problems. If Sun recommend 1 it
> > then it seems odd that Informix recommend 64 in the release notes
> >
>
> Last time I looked more closely at the release notes- informix do not
> recommend 64. 64
> is what was used on the machine that Informix did their testing!!

Fair point. But if the engine just won't start and you end up logging
a call, one of the opening questions is 'have you set /etc/system as
per the release notes'

>
> Use 1 as their is other software (Sonnet for printing?) which needs small
> shared memory
> segments.
>
> Can someone get Informix to change their release notes? And get rid of
> enable_sm_wa
> as well. Surely Informix no longer use Solaris 2.4 for porting and it is
> not a supported
> platform any more?
>
> > Jonathan Leffler wrote:
> > >
> > > Paul Watson wrote:
> > >
> > > > AFAIR the shmmin of 1 is required for powerd, if you are not using
> > > > power management then leave it at 64
> > >
> > > I agree with the first half - powerd is the primary system user. On
> > > Solaris 7, I set it to 16 because powerd used a somewhat bigger number
> > > (28 bytes?). On Solaris 8, powerd only uses 4 bytes. Informix
> > > doesn't care what the value is as long as it is small enough to permit
> > > the smallest segment IDS wants to allocate - which would probably be
> > > in the 1KB range.
> > >
> > > I disagree with the conclusion - if Sun recommends 1, use 1. It's
> > > their o/s. Setting it to 1 won't harm Informix - and not setting it
> > > to 1 might harm your system.
> > >
> > > > jjjj wrote:
> > > >> I have Informix dynamic server 9.20.UC1 installed on Sun Solaris
> > > >> machine. The shmmin setting in /etc/system is set to 64. Sun
> > > >> recommends to set it to 1. Can anyone tell me if it is ok to
> > > >> change the value to 1? Any addintional information about it is
> > > >> welcome.
> > >
> > > --
> > > Jonathan Leffler #include <disclaimer.h>
> > > Email: jleffler@earthlink.net, jleffler@us.ibm.com
> > > Guardian of DBD::Informix v2003.04 -- http://dbi.perl.org/
> >
> > --
> > Paul Watson #
> > Oninit Ltd # Growing old is mandatory
> > Tel: +44 1436 672201 # Growing up is optional
> > Fax: +44 1436 678693 #
> > Mob: +44 7818 003457 #
> > www.oninit.com #

--
Paul Watson #
Oninit Ltd # Growing old is mandatory
Tel: +44 1436 672201 # Growing up is optional
Fax: +44 1436 678693 #
Mob: +44 7818 003457 #
www.oninit.com #

Paul Watson <paul@oninit.com> wrote in message news:<3FB3A455.198136BB@oninit.com>...
> powerd (1M) is the power management daemon, you get an EINVAL if
> you attempt to start it with shmmin over 68. There is no need
> for powerd to running unless you want the machine to shutdown
> automatically due to idle time or low battery etc.
>
> I believe powerd became default in 2.4 but that was a while back. But
> I suspect that was when the /etc/system recommendations from Informix
> were set as they still mentions enable_sm_va
>
> Jonathan Leffler wrote:
> >
> > Paul Watson wrote:
> >
> > > AFAIR the shmmin of 1 is required for powerd, if you are not using
> > > power management then leave it at 64
> >
> > I agree with the first half - powerd is the primary system user. On
> > Solaris 7, I set it to 16 because powerd used a somewhat bigger number
> > (28 bytes?). On Solaris 8, powerd only uses 4 bytes. Informix
> > doesn't care what the value is as long as it is small enough to permit
> > the smallest segment IDS wants to allocate - which would probably be
> > in the 1KB range.
> >
> > I disagree with the conclusion - if Sun recommends 1, use 1. It's
> > their o/s. Setting it to 1 won't harm Informix - and not setting it
> > to 1 might harm your system.
> >
> > > jjjj wrote:
> > >> I have Informix dynamic server 9.20.UC1 installed on Sun Solaris
> > >> machine. The shmmin setting in /etc/system is set to 64. Sun
> > >> recommends to set it to 1. Can anyone tell me if it is ok to
> > >> change the value to 1? Any addintional information about it is
> > >> welcome.
> >
> > --
> > Jonathan Leffler #include <disclaimer.h>
> > Email: jleffler@earthlink.net, jleffler@us.ibm.com
> > Guardian of DBD::Informix v2003.04 -- http://dbi.perl.org/

According to Informix, the value can be the smallest value OS can
support. Hence, no problem changing it to 1.

jjjj wrote:
> I have Informix dynamic server 9.20.UC1 installed on Sun Solaris machine.
> The shmmin setting in /etc/system is set to 64. Sun recommends to set it to
> 1.
> Can anyone tell me if it is ok to change the value to 1?
> Any addintional information about it is welcome.
>
>
According to Informix, the value can be the smallest value OS can
support. Hence, no problem changing it to 1.