I've tested the behavior of the thread that waits for the LiveUpdate to
be finished, and it does get signaled and exit cleanly when the
LiveUpdate is GCed instead.
Made finishedLiveUpdate wait for the thread to finish updating the
database.
There is a case where GC doesn't happen in time and the database is left
with a live update recorded in it. This should not be a problem as such
stale data can also happen when interrupted and will need to be detected
when loading the database.
Balanced preferred content expressions now call startLiveUpdate.
Each command that first checks preferred content (and/or required
content) and then does something that can change the sizes of
repositories needs to call prepareLiveUpdate, and plumb it through the
preferred content check and the location log update.
So far, only Command.Drop is done. Many other commands that don't need
to do this have been updated to keep working.
There may be some calls to NoLiveUpdate in places where that should be
done. All will need to be double checked.
Not currently in a compilable state.
A new repo that has no location log info yet, but has an entry in
uuid.log has 0 size, so make RepoSize aware of that.
Note that a new repo that does not yet appear in uuid.log will still not
be displayed.
When a remote is added but not synced with yet, it has no uuid.log
entry. If git-annex maxsize is used to configure that remote, it needs
to appear in the maxsize table, and the change to Command.MaxSize takes
care of that.
When the specified number of copies is > 1, and some repositories are
too full, it can be better to move content from them to other less full
repositories, in order to make space for new content.
annex.fullybalancedthreshhold is documented, but not implemented yet
This is not tested very well yet, and is known to sometimes take several
runs to stabalize.
Might want to make --rebalance turn balanced=group:N where N > 1
to fullysizebalanced=group:N. Have not yet determined if that will
improve situations enough to be worth the extra work.
The use of catObjectStream is optimally fast. Although it might be
possible to combine this with git-annex branch merge to avoid some
redundant work.
Benchmarking, a git-annex branch that had 100000 files changed
took less than 1.88 seconds to run through this.
At this point the RepoSize database is getting populated, and it
all seems to be working correctly. Incremental updates still need to be
done to make it performant.
Including locking on creation, handling of permissions errors, and
setting repo sizes.
I'm confident that locking is not needed while using this database.
Since writes happen in a single transaction. When there are two writers
that are recording sizes based on different git-annex branch commits,
one will overwrite what the other one recorded. Which is fine, it's only
necessary that the database stays consistent with the content of a
git-annex branch commit.
Plan is to run this when populating Annex.reposizes on demand.
So Annex.reposizes will be up-to-date with the journal, including
crucially journal entries for private repositories. But also
anything that has been written to the journal by another process,
especially if the process was ran with annex.alwayscommit=false.
From there, Annex.reposizes can be kept up to date with changes made
by the running process.
This is very innefficient, it will need to be optimised not to
calculate the sizes of repos every time.
Also, fixed a bug in balancedPicker that caused it to pick a too high
index when some repos were excluded due to being full.
