[Info-vax] Large mailboxes

[Arne Vajhøj]

On 11/26/2020 1:27 PM, Arne Vajhøj wrote:
> On 11/26/2020 11:30 AM, Marc Van Dyck wrote:
>> So my question is, why this limitation ? Is it just because when this
>> interface was written, noone imagined that there could ever be a
>> mailbox with more than 64k outstanding messages ? Or am I really going
>> to break something other than this counter if I try loading more
>> than 64k messages ?
> 
> I don't know.
> 
> But it seems likely that noone imagined it being a problem.
> 
> It uses non-paged pool. How big was available non-paged pool on
> VAX systems?
> 
> My guess is that available non-paged pool divided by a
> normal message size would fit into 16 bit.

I could add that as a rule of thumb I would
only use VMS mailboxes (or Windows pipes or
*nix unix sockets) to buffer hundreds or a
few thousands of messages.

If I needed hundreds of thousands or
millions I would look for a message queue
(and if I needed billions I would look at
Kafka).

Arne