Le 2020-05-11 17:10, Eli Schwartz a écrit :
On 5/11/20 10:27 AM, guilla...@manjaro.org wrote:
Hi Allan, Hi Anatol,
I was looking to this new multiplexed implementation and I found some
problems:
1) This implementation can lead to download databases from different
servers, I think it can't be a problem if they are not synced
This should already be the case in the single-download version too, no?
I agree and nothing can be done except ensuring all databases are
downloaded
from the same server.
2) Differents download payloads are created for databases and its
signature files, this can this time lead to download the database and
its signature from differents server, I'm sure it's not wanted.
3) Because signature files have their own download payloads, if the
signature is missing on a the first server (e.g. database signature is
optional), all next servers will be tried and all will give the same
error.
re 2) I cannot remember offhand if this was already the case, but
anyway
it's not impossible for one to download the database successfully from
one mirror, then get a sudden network issue on the signature. Falling
back to a second server for optional signatures will just lead to
download errors (which are ignored for sigs), and for required
signatures it will fail the signature check the same way failure to
download the signature at all would fail, because one way or another we
*need* an updated signature.
I agree that the signature checking will fail anyway but we don't need
to start
downloading a signature if we know it's from a different server than the
one used for the database.
re both 2) and 3) I guess this could be optimized in the database
download handling to abort on the first 404 but fall through to
additional servers for connection failures. I'm not sure whether this
would be a good thing... how would we detect mirrors that can be
connected to, but no longer host any pacman repos? Checking 5 mirrors
for 404 errors isn't much of an issue.
I guess it could also solve this error I got:
error: failed retrieving file 'core.db.sig' from
mirror.epiphyte.network
: Could not resolve host: mirror.epiphyte.network
error: failed retrieving file 'testing.db.sig' from
mirror.epiphyte.network : Could not resolve host:
mirror.epiphyte.network
error: failed retrieving file 'extra.db.sig' from
mirror.epiphyte.network : Could not resolve host:
mirror.epiphyte.network
error: failed retrieving file 'community-testing.db.sig' from
mirror.epiphyte.network : Could not resolve host:
mirror.epiphyte.network
error: failed retrieving file 'community.db.sig' from
mirror.epiphyte.network : Could not resolve host:
mirror.epiphyte.network
error: failed retrieving file 'multilib.db.sig' from
mirror.epiphyte.network : Could not resolve host:
mirror.epiphyte.network
error: failed retrieving file 'multilib-testing.db.sig' from
mirror.epiphyte.network : Could not resolve host:
mirror.epiphyte.network
But I'd already solved this one by removing the dead mirror from the
bottom of my mirrorlist (it used to be a pretty good fallback one).
When
all mirrors fail in the more normal manner at retrieving a signature,
there's no UI results.
Yes it should be optimized, I think we should simply not retry to
download a
signature after a failure.
This is the point that makes me first inspect this code, it leads to try
to download the
signature from every mirror for every database so it's can really slow
down the process.
I really wanted to suggest a patch but I didn't find a easy way
(understand a small patch) to fix it and I would like your opinion on
point 1) first.
Regards,
Guillaume.
