Re: Please document the caching and its user options

[Ihor Radchenko <yantar92@posteo.net>]

Daniel Clemente <n142857@gmail.com> writes:

> Thanks. I'm not sure about the "unless" part here:
>
>> Persisting the cache to disk […]
>> It is not recommended if the Org files
>> include sensitive data, unless the data is encrypted via `org-crypt'.")
>
> I first mentioned org-crypt because users of org-crypt may be
> surprised if they see encrypted data stored unencrypted in disk, due
> to this cache.

No unencrypted data should be stored in the cache _on fs_.
If it does get stored, it is a bug that should be reported.

> A user has somefile.org which contains some headers marked with the
> "crypt" tag. Only those headers are encrypted. The org-element cache
> may now cache the whole file, including the encrypted headers (this is
> ok). Now the user temporarily decrypts the encrypted header, works on
> it some time (including closing the file and opening it again) then
> encrypts the section again. During the time that the header was
> unencrypted, the org-element cache was storing information about
> unencrypted data in ~/.cache/org-persist, which could even be a remote
> server (NFS, SMB etc), not as private as the org file itself.

Nope. Storing to disk only happens when you kill the buffer and before
exiting Emacs. At that point, org-crypt must take care about
re-encrypting everything.

> The rest of the documentation change seems good, it improves things.
> I would just mention the shortcomings or disclaimers, if there are.
> For instance I worry about what may happen when different Emacs
> processes load the same Org files at the same time (e.g. I run several
> automated batch export jobs). And I guess that having a disk cache
> creates new problems, like when in a web browser a simple F5 won't
> refresh and you need S-F5.
> But if there are no shortcomings (i.e. all operations will always use
> up to date information and everything will keep working as usual when
> you enable on-disk cache), it's ok like it is. It's also good if it's
> explicitly mentioned. It could also be mentioned somewhere else, like
> in a cache section in the manual, if it gets one.

Multiple Emacs instances are handled correctly. I do not see much
point documenting that things are working as expected.

-- 
Ihor Radchenko // yantar92,
Org mode contributor,
Learn more about Org mode at <https://orgmode.org/>.
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