[Info-vax] New OpenSSL update from HP

[Simon Clubley]

On 2015-06-15, David Froble <davef at tsoft-inc.com> wrote:
> Simon Clubley wrote:
>> On 2015-06-15, David Froble <davef at tsoft-inc.com> wrote:
>>> Ok, I've never written a web server, yet.  If I was to do so, I'd 
>>> seriously look at detached processes rather than sub-processes.  Why? 
>>> Because once you assign the worker process a task, perhaps you'd want it 
>>> to complete, regardless of whatever the web server does.
>>>
>> 
>> What happens if you need to shutdown/restart the web server and need
>> to _guarantee_ that all related processes have terminated as part of
>> of the shutdown process ?
>> 
>
> Couple of issues there.
>
> First, a worker process lifetime should be measured in fractions of a 
> second, or a couple seconds at most.
>
> The listener could keep track of the PIDs that it created, and a 
> shutdown command could terminate them in the chosen manner.
>
> That said, it's been my impression that web server transactions are 
> stateless, (if I understand that term), and usually occur in a rather 
> short time period, such as a fraction of a second.  Do you have examples 
> of when a worker process would remain active for an extended period of 
> time?  I'm curious.
>

I was responding to the specific technical issues around your desire
to make them detached processes instead of subprocesses.

Also, connections remain open by default after the initial request has
been completed; these are called persistent connections. See:

	https://en.wikipedia.org/wiki/HTTP_persistent_connection

In order to implement this functionality, your detached process would
have to remain around after the initial request has completed and they
would not automatically die (unlike with subprocesses) if the parent
web server process croaked due to some internal bug.

Simon.

-- 
Simon Clubley, clubley at remove_me.eisner.decus.org-Earth.UFP
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