[Info-vax] V9.2-1 Page file size

[Arne Vajhøj]

On 2/24/2024 7:33 PM, Chris Townley wrote:
> On 25/02/2024 00:12, Arne Vajhøj wrote:
>> On 2/24/2024 2:18 PM, Chris Townley wrote:
>>> Just upgraded a VM from 9.2-1 to 9.2-2 which seemed to have worked well.
>>>
>>> Bearing in mind this us just a hobbyist system, when I created the VM 
>>> I gave it 8GB memory, and an 8Gb system disk
>>>
>>> That was fine, and it created a 2Mb pagefile, not expecting it to be 
>>> used.
>>>
>>> The autogen run at the end of the upgrade obviously though this was 
>>> rubbish, so tried to create an 8Gb pagefile on the system disk. 
>>> Clearly it couldn't, so it created one of over 4Gb - leaving me with 
>>> 120Mb free.
>>>
>>> It also wanted an 8Gb dumpfile.
>>>
>>> Is any of this sensible?
>>
>> I believe that is one of the differences between Windows and VMS. On
>> Windows plenty of RAM and no/small pagefile works fine. VMS want
>> pagefile backing of virtual memory even if it is not likely to
>> need it. And running out of pagefile space is bad - very bad. So I got
>> 1 x 8 GB pagefile on my VMS x86-64 and 3 x 1 GB pagefile on
>> my VMS Alpha (can't remember what I have on my VMS Itanium).
> 
> But VSI recommended 8Gb memory, and an 8Gb system disk. So how do we fit 
> that in? Especially if they want another 8Gb for the dump file

I don't get it. 8 GB RAM makes sense. I would go for 20/30/40/50 GB
disk.

I don't think you need that big a dump file. It may want that big
a dump file, but if I remember correctly then VMS writes a subset
of data if the dumpfile is not big enough for all data. Obviously
if you want perfect analysis of a crash, then a full size dumpfile
may be nice, but ...

Arne