* 2020-11-15 10:21:18+03, Jean Louis wrote:

> I have 50000+ Maildir folders relating to 50000+ conversations and
> many more email messages.

Yes, some of us like storing all the mail we have received. I'll
"advertise" my preferred system.

    $ notmuch count
    458078

All those mails are currently in 14 Maildir directories, by the year of
the mail message, so that a single file system directory don't grow too
much.

(At some point I had _all_ mail files in a single Maildir directory
which is perfectly fine for Notmuch. However, some file system tools
might start to slow down when one directory has hundreds of thousands of
files. It's probably better to split mail file somehow. Thus, I nowadays
split mail files to differect directories by year. Anyway, for Notmuch
it doesn't mean anything.)

> Maildir format is number one choice for me, and I wish Emacs could be
> able to handle that, but it does not.

Or Emacs doesn't need to handle mail files at all: Notmuch Emacs
interface works by calling Notmuch which does the work through its
database. So when I open a virtual folder "emacs.help" in the user
interface it triggers preconfigured search with terms like:

    ( to:help-gnu-emacs@gnu.org OR List:help-gnu-emacs ) AND date:90days..

Search term "List" is for indexed List-Id headers in my system.

> My strategy for handling emails is that each email address has its
> Maildir folder. That means by one key press in Mutt (by configuration)
> I can access all previous conversations related to that email address.
> It is blazing fast compared to anything I have tested in Emacs and I
> have tested them all.

Another approach for fast mail handling is to index all mail like
Notmuch. Searching doesn't read actual mail files; it uses the database
indexes. Only when user wants to display a mail the actual file is
opened in the file system. That is always fast and it doesn't matter
where the mail is located in the file system.

    $ time notmuch search from:"Jean Louis" AND date:2018..2019 >/dev/null

    real    0m0,037s
    user    0m0,033s
    sys     0m0,004s


-- 
/// Teemu Likonen - .-.. https://www.iki.fi/tlikonen/
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