On Thu, Mar 26, 2020 at 01:16:22PM +0200, Panu Matilainen wrote:
On 3/26/20 1:02 PM, Zbigniew Jędrzejewski-Szmek wrote:
>On Mon, Mar 16, 2020 at 11:22:47AM -0400, Ben Cotton wrote:
>>=== Upgrading ===
>>* Ability to upgrade is not affected
>>* After upgrade completes, manual action (rpmdb --rebuilddb) will
>>probably be needed to convert to sqlite. Alternatively user can change
>>configuration to stay on BDB.
>Do I understand correctly:
>- without the manual step, users will remain on the old format
>- with the old format, in F33 everything will still work fine, but
> after upgrade to F34, the database will become read-only
>Why is an automatic 'rpmdb --rebuilddb' not part of upgrade plan?
To repeat what I said in https://pagure.io/fesco/issue/2360
thanks for quick answer and sorry for double-posting. I started
reading the fesco ticket, then the change page, then the discussion
here, and forgot to read the rest of the comment on the ticket.
I also posted there, but I think it's better to discuss here.
I'll copy my post from there here, sorry for the mess.
I left it open on purpose (note the "probably" in there) as
would be any number of ways to achieve the rebuild with varying
degrees of automation and opt-out opportunities, depending on what
is actually desireable for Fedora.
One possibility could be adding a rebuild step to dnf system-upgrade
plugin, rebuilding the db after distro upgrades is not a bad idea
regardless of db format changes (at least BDB performance would
gradually degrade unless rebuilt every now and then). That would
leave people doing the (unspeakable) distro-sync upgrade to deal
with database format manually, which might be just the right balance
of freedom. Or not, I dunno. Other possibilities include planting a
one-shot service that does the db rebuild on the next reboot and
decommissions itself afterwards in the rpm package itself. Other
variations certainly exist.
Suggestions welcome, just as long as you don't suggest rebuilding
from rpm %posttrans :)
Right. I realize %posttrans is not a good idea. But *some* mechanism
is necessary, because without that the change will mostly be a noop
for most users. So I think this needs to be decided somehow.
Quoting from the FESCo ticket:
About the various implementation options:
- in dnf system-upgrade: this does not cover normal 'dnf
--releasever=33 upgrade' upgrades (as you mentioned earlier), but it
also does not cover packagekit upgrades. It'd also create a
previous-release-blocker(s) and previous-previous-release-blockers(s),
since the changes would need to be deployed in F32 and F31. Also
note that the last time when the upgrade plugins run code is in
upgrade phase between two reboots, and the plugin is running
pre-upgrade code. This code would then invoke post-upgrade rpm. It's
certainly doable, but seems a bit funky.
- a one-shot service: this is easier to implement, it just needs to
happen in one place. The hard part is making sure that the machine
does not get reboot while the upgrade is happening. This is in
particular a problem with VMs and containers. The rebuild should be
wrapped with systemd-inhibit and other guards to make it hard to
No matter how it wrapped, is the upgrade itself atomic? Having the new
db built under a temporary file name and then atomically rename(2)d
into place would be ideal.