dnf --refresh reverts to older metadata (was: Re: dnf update vs Software Udpates)

[Michael Schwendt]

On Tue, 18 Aug 2015 05:54:07 -0400 (EDT), Honza Šilhan wrote:

> File a bug, if you care, please.

And if I don't file a bug, I don't care?
That would be an odd way to put it. =:-/

Would you rather prefer silence and people returning to another distribution? 
I mean, it is not clear yet whether mirror manager is the culprit, is it?

Also, it's very unlikely that the dnf developers use only bugzilla for all project
management, such as todo lists and milestone target details. Now that you've learned
there is some fundamental problem, it should be put onto some internal todo list
to schedule some proof-reading of the implementation and sit together with the
mirror manager guys. Very important would be to verify all the stuff around the
metalink XML parsing and evaluating, especially the age/timestamp/checksum/alternates.

Adding more helpful debug output would be an idea, too.
Certainly it should be possible to print metalink data age, which would be
much more relevant than the time of the last metadata expiration check.

> + output of these command sequence (to see which mirror is picked)
> # export LIBREPO_DEBUG=1 && dnf update --assumeno
> # export LIBREPO_DEBUG=1 && dnf update --assumeno --refresh
> # dnf clean metadata
> # export LIBREPO_DEBUG=1 && dnf update --assumeno

This does not print "which mirror is picked".

It does not print anything helpful at all.

I would expect debug information to include some details about the metalink server
response, the metadata checksum and the metadata age, and stuff like that.

| Librepo version: 1.7.16 with CURL_GLOBAL_ACK_EINTR support (libcurl/7.44.0 NSS/3.19.3 Basic ECC zlib/1.2.8 libidn/1.32 libssh2/1.6.0 nghttp2/1.2.0)
| lr_download: Target: file:///etc/dnf/dnf.conf (-)
| select_next_target: Selecting mirror for: file:///etc/dnf/dnf.conf
| prepare_next_transfer: URL: file:///etc/dnf/dnf.conf
| add_librepo_xattr: Cannot set xattr user.Librepo.DownloadInProgress (fd: 5): Operation not supported
| lr_download: Downloading started
| check_transfer_statuses: Transfer finished: file:///etc/dnf/dnf.conf (Effective url: file:///etc/dnf/dnf.conf)
| Fedora - Rawhide - Developmental packages for t 1.4 MB/s |  43 MB     00:29    
| Adobe Systems Incorporated                       23 kB/s | 1.8 kB     00:00    
| Last metadata expiration check performed 0:00:00 ago on Tue Aug 18 12:25:42 2015.
| Dependencies resolved.

> Michael, have you run all these commands at one moment or after 1 day
> breaks?

That can be seen in dnf's output:
https://lists.fedoraproject.org/pipermail/users/2015-August/464144.html

Excerpt:

# dnf update
Last metadata expiration check performed 1:19:01 ago on Fri Aug 14 11:29:15 2015.
[...]
Install   3 Packages
Upgrade  76 Packages
Remove    3 Packages
[...]

# dnf update --refresh
Adobe Systems Incorporated                       21 kB/s | 1.8 kB     00:00    
Fedora - Rawhide - Developmental packages for t 1.5 MB/s |  43 MB     00:29    
Last metadata expiration check performed 0:00:13 ago on Fri Aug 14 12:48:43 2015.
[...]
Install   3 Packages
Upgrade  76 Packages
Remove    3 Packages
[...]

# dnf update --refresh
Fedora - Rawhide - Developmental packages for t 1.4 MB/s |  43 MB     00:30    
Adobe Systems Incorporated                       21 kB/s | 1.8 kB     00:00    
Last metadata expiration check performed 0:00:00 ago on Fri Aug 14 12:50:08 2015.
[...]
Upgrade  50 Packages
[...]


As one can see, a bit more than a minute between those two last runs.
Then, a day later, only "dnf clean metadata" lead to fetching new metadata:
https://lists.fedoraproject.org/pipermail/users/2015-August/464173.html


Some hours later when I replied to another mail in the thread, I could reproduce
the "--refresh reverts to old metadata" problem with two runs one minute after
eachother:
https://lists.fedoraproject.org/pipermail/users/2015-August/464184.html

# dnf update --refresh
Adobe Systems Incorporated                       21 kB/s | 1.8 kB     00:00    
Fedora - Rawhide - Developmental packages for t 1.5 MB/s |  43 MB     00:29    
Last metadata expiration check performed 0:00:11 ago on Sat Aug 15 19:21:15 2015.
[...]
Install    4 Packages
Upgrade  168 Packages
Remove     3 Packages
[...]

# dnf update --refresh
Adobe Systems Incorporated                       13 kB/s | 1.8 kB     00:00    
Fedora - Rawhide - Developmental packages for t 1.4 MB/s |  43 MB     00:29    
Last metadata expiration check performed 0:00:39 ago on Sat Aug 15 19:22:31 2015.
[...]
Install    4 Packages
Upgrade  111 Packages
Remove     3 Packages
[...]