[Info-vax] VSI strategy for OpenVMS

[Arne Vajhøj]

On 9/16/2021 5:10 PM, Dave Froble wrote:
> On 9/16/2021 2:45 PM, Arne Vajhøj wrote:
>> On 9/15/2021 1:00 AM, Phillip Helbig (undress to reply) wrote:
>>> In article <shr7f4$tnu$1 at gioia.aioe.org>, =?UTF-8?Q?Arne_Vajh=c3=b8j?=
>>> <arne at vajhoej.dk> writes:
>>>>>> Businesses are interested in application availability. They
>>>>>> do not care whether that is provided by OS features or
>>>>>> application features.
>>>>>
>>>>> They should care if they have to hire twice as many people to 
>>>>> implement
>>>>> the non-VMS solution.
>>>>
>>>> But why should they need to hire more people??
>>>>
>>>> Let us take Rdb vs Oracle DB aka Classic with RAC (real RAC
>>>> not RAC One). Both use a DLM but Rdb use VMS DLM while Oracle DB
>>>> RAC use its own DLM.
>>>>
>>>> Does it matter for developers or operations? Not really.
>>>
>>> Have you ever worked anywhere where one tried to emulate the
>>> functionality of VMS with regard to clustering, availability, and so on
>>> with non-VMS hardware and software?
>>
>> It was a very specific example where the same functionality is provided
>> by either DLM in the application or in the OS.
>>
>> I don't see why it would require more people to manage when
>> it is in the application.
> 
> If it's in the application, who puts it there and maintains it?
> 
> If it's in the OS, the required people for maintenance is zero.

I cannot follow you.

If we look at the stacks:

                           Rdb        Oracle RAC
business application      X          X
RDBMS                     Oracle     Oracle
DLM                       VSI        Oracle
OS                        VSI        whoever

The difference is that some work get moved from OS vendor to Oracle.

But Oracle is probably not unhappy about that, because the
cost of maintaining the DLM is offset by the savings from
having the same DLM API across OS'es.

Arne