todo item based on behavior yoh showed me

doc/todo/inneficiency_on_slow_filesystems_opening_nonexistant_journal_files.mdwn

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+`git-annex info uuid` was observed to be slow on a slow NFS, because
+it is opening lots of .git/annex/journal files that DNE. So does
+`git annex find --in remote`.
+
+Normally the journal is empty, but each query of a file from the git-annex
+branch still tries to open the corresponding journal file.
+
+It seems that this could be improved by making such query commands
+either commit the journal to the branch once at startup, or check if the
+journal is empty, and once there's known to be nothing in the journal,
+avoid opening files from there.
+
+But: Concurrency. Another process may be writing changes to the git-annex
+branch, via the journal, and so this would be a behavior change. Mostly
+that seems acceptible, because there's no defined ordering of events in
+such a situation, and this change only makes it so that the writes
+effectively always come after the reads.
+
+But: Batch jobs. When a git-annex command is run in a batch mode,
+its caller can currently safely expect that running some other command,
+that modifies the git-annex branch, followed by asking the batch
+mode command to query it will yield a result that takes the earlier write
+into account.
+
+So, this optimisation seems it would be limited to commands that
+are not in batch mode and do strictly read-only queries. Which seems a bit
+hard to plumb through to the git-annex branch reading code.
+
+An easier alternative would be an option that bypasses reading the journal.
+But maybe there's some other, better way to avoid this slow case?
+--[[Joey]]