Re: Gnus: caching message headers?

[Madhu <enometh@meer.net>]

* Eric Abrahamsen <87lfheefq4.fsf@ericabrahamsen.net> :
Wrote on Sat, 12 Sep 2020 16:29:39 -0700:

> Ozhap <ozhap@vollbio.de> writes:
>
>> Eric Abrahamsen <eric@ericabrahamsen.net> writes:
>>
>>> Ozhap <ozhap@vollbio.de> writes:
>>>
>>>>>> "If I read an article while plugged, do they get entered into the
>>>>>> Agent?"
>>>>>>
>>>>>> *No*.  If you want this behavior, add
>>>>>> `gnus-agent-fetch-selected-article' to `gnus-select-article-hook'.
>>>>
>>>>> That Info page could be more explicit that `gnus-agent-cache' means that
>>>>> articles *will* be added to the agent as they are read.
>>>>
>>>> That's how it stands now, but in info '(gnus)Agent as Cache' it says:
>>>>
>>>> "..Gnus normally only downloads *headers* once, and stores them in the
>>>> Agent"
>>>>
>>>> "Articles are *not* cached in the Agent by default though (that
>>>> would potentially consume lots of disk space), but if you have
>>>> *already downloaded an article into the Agent*, Gnus will not
>>>> download the article from the server again but use the locally
>>>> stored copy instead."
>>>>
>>>> I did some digging, and this behaviour was changed due to bug#8502
>>>> where Lars concludes (erroneously, on the face of it):
>>>>
>>>>> Let's see...  caching...  so if you're online (in an agentised
>>>>> group) and select an article, you want the article to be saved in
>>>>> the Agent directory?  That sounds eminently reasonable, and I
>>>>> thought that was supposed to happen, but I can't find any code for
>>>>> doing that...  hm...  Nope.
>>>>
>>>> Ref:
>>>> https://debbugs.gnu.org/cgi/bugreport.cgi?bug=8502
>>>
>>> If I were you I would do this up as a proper bug report. Lars is now
>>> an Emacs maintainer, so he'll be obliged to look at it :)
>>>
>>> One way or another there is a mismatch between documentation,
>>> customization options, and actual observed behavior. I think if you
>>> can make it clear what that mismatch is, we stand a good chance of
>>> getting it fixed.
>>
>> Here you go. I think I did good :)
>> https://debbugs.gnu.org/cgi/bugreport.cgi?bug=43356
>
> I saw it, I agree it's good!

Lars followed the instructions like a good boy and and has obsoleted
gnus-agent-store-article and removed that functionality.

| commit def34a20766ea5179afd5e5ed090a2b86fcccb5e
| Author:     Lars Ingebrigtsen <larsi@gnus.org>
| AuthorDate: Sun Sep 13 16:46:11 2020 +0200
|
|     "If I read an article while plugged, do they get entered into the
|     Agent?"
|
|          *No*. If you want this behavior, add
|          `gnus-agent-fetch-selected-article' to
|          `gnus-select-article-hook'.
|


However the overhead of calling gnus-agent-fetch-selected-article is too
much in my 100s of (NNTP) news groups and the several thousands of
articles with complicated reading history. "Yuuge lists of gnus cons
data structures".  The overhead is not acceptable.

The earlier behaviour was exactly what I wanted for NNTP (I dont use
gnus for mail) and I have been using the feature on selective servers
ever since it was added, relying on gnus to back up my memory (If I read
an article gnus can help me remember where I read it). I don't give a
shit about gmail users and I'd suggest reverting it unobsoleting
gnus-agent-store-article and yet another switch for those who want to
keep the original very useful behaviour code path. For those who prefer
to control their own data instead of selling it (along with their access
patterns and their souls) to google.