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mds: drop partial entry and adjust write_pos when opening PurgeQueue #14447
At tail journal, there can be partial written entry. Before appending
For PurgeQueue journal, we don't replay the whole journal when MDS
changed the title from
mds: don't probe end of purge queue log
[DNM ]mds: don't probe end of purge queue log
Apr 11, 2017
I think we could probably just avoid all partial entries by making the journaler_allow_split_entries setting configurable on a per-instance basis, and then setting it on the PurgeQueue Journaler instance. If we are always using a non-striped layout for the purge queue journal, then we should never see a split entry, right?
The PurgeQueue change looks correct to me, but I'm not sure the Journaler optimisation is really necessary (and it adds another variable to an already slightly complicated class).
Since we already write out the header at journaler_write_head_interval, I'm not sure what the concern is about the difference between the header write_pos and the probed write_pos getting too large?