topic Re: Memory upgrade in Operating System - OpenVMS

Memory upgrade

Guillou_2 — Tue, 11 May 2004 04:08:15 GMT

Hi,

We plan to upgrade memory (128 mo -> 256 mo)on our vax 6000-510 (vms 6.2).

Is there any particular actions to do after inserting the new memory or VMS recognizes and uses it automatically?

Thanks in advance for your help.

Re: Memory upgrade

Mobeen_1 — Tue, 11 May 2004 04:19:40 GMT

Guillo,
I am not aware of any special actions that you would be required to perform after you upgrade the memory. Just need to power down make the replacement and then boot up the system. Once the system is up, i would advise that you do the following

1. show mem/full
(Make sure that the memory is 256MB)

2. Run AUTOGEN
As the memory has changed, i think it
is never bad to run Autogen.

Let me know if you have any specific questions

regards
Mobeen

Re: Memory upgrade

Uwe Zessin — Tue, 11 May 2004 04:20:52 GMT

There is a system parameter (on the VAX it is PHYSICALPAGES?) that can be used to limit the amount of memory that VMS is going to use. On earlier systems it was resized by AUTOGEN to the amount of current memory.

If I recall correctly, starting with V6.0 or V6.1, VMS will automatically use the full amount of memory. You should still run AUTOGEN, so that VMS can adjust other memory-related parameters.

Re: Memory upgrade

Ian Miller. — Tue, 11 May 2004 05:30:38 GMT

Ensure PHYSICALPAGES is not set explictly in MODPARAMS.DAT and if not VMS will recogise the extra memory. Ensure autogen feedback is saved when you shutdown the system to install the memory and after the first boot run autogen with feedback to ensure best use of the memory. If the autogen changes any non-dynamic parameters you will have to reboot again to use the new values.

Re: Memory upgrade

John Gillings — Wed, 12 May 2004 16:53:30 GMT

>If I recall correctly, starting with V6.0 or V6.1, VMS will automatically use the full amount of memory.

It's the other way around. Pre V6 OpenVMS would automatically configure all available physical memory on any reboot. Post V6 you need to run AUTOGEN to make the operating system sees the extra memory after an upgrade. It was a consequence of adding support for larger memory VAXes - The maximum value for PHYSICALPAGES was increased. Old behaviour was to default PHYSICALPAGES to the (then) maximum value. New behaviour is for AUTOGEN to set PHYSICALPAGES to the amount found at the time it's run.