Re: automatic Agentizing of servers (was: Summary buffer

[Simon Josefsson <jas@extundo.com>]

Harry Putnam <reader@newsguy.com> writes:

> Simon Josefsson <jas@extundo.com> writes:
>
>> But it doesn't rule out the possibility that I'm wrong. :-)
>>
>> The auto-agentification is rather simplistic, basically I believe it
>> now just work like:
>>
>> IF NOT EXISTS ~/News/agent/lib/servers THEN
>>   DOLIST (cons gnus-select-method gnus-secondary-select-methods)
>>     method = (gnus-method-to-server LISTEL)
>>     IF CAR(method) MEMBER OF gnus-agent-auto-agentize-methods
>>        ADD method TO gnus-agent-covered-methods
>>   WRITE gnus-agent-covered-methods INTO ~/News/agent/lib/servers
>
> Maybe its been explained before but I'm having trouble understanding
> why we need any auto agentization.  Seems like it should always
> require a `J a' on the server.  What is really saved or made better
> by having it automatic?

The auto-agentification make the use-agent-as-cache the default
behaviour, for remote backends.  Most MUAs these days cache the
equivalent of NOV information in groups, and I think it is useful.  If
nntp/nnimap groups were not auto-agentified, or if the user removed
those servers from the agent, entering groups with thousands of
articles would download the NOV data every time you enter the group,
this can be slow.  With the agent NOV cache, entering even groups with
20000 articles is rather fast, because almost nothing have to be
transfered over the network.

So essentially the reason for auto-agentifying some servers is that it
improves performance, and doesn't (shouldn't) affect anything else.

Steinar Bang <sb@dod.no> writes:

> Ie. I can live with today's behaviour as long as I don't have to
> remove agentizing every time I start Gnus, but I don't get why it has
> to be this way.

Hm, maybe if we look at it from the reverse point of view: why don't
you want the nntp/nnimap backends in the agent?  Does it cause any
problems?  Don't you find entering large nnimap/nntp groups slow?
I.e., waiting for all NOV data to be downloaded?  If the servers are
agentified, only the first time you enter a group will be slow.

(Btw, nnimap has its own NOV cache, but it is disabled when the agent
is enabled.  Perhaps it should only be disabled if the current server
is not in the agent, instead.  But even so, having two NOV caches
within Gnus just make it more difficult to maintain; it is easier to
fix bugs in one NOV cache than to fix them in two.  So it would be
better if the agent NOV cache was used all the time, which is what
auto-agentification achieves.  You can enable the nnimap-specific NOV
cache by toggling `nnimap-nov-is-evil'.)