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[[!tag open_issue_gnumach open_issue_hurd]]

Also filed as [[!GNU_Savannah_bug 29292]].

\#hurd, 2010, end of May / beginning of June

    [runnign sync, but sill unclean filesystem at next boot]
    <slpz> guillem: when libpager syncs an object, it sends an m_o_lock_request
      and waits (if the synchronous argument was specified) for a
      m_o_lock_completed. But m_o_lock_completed only means that dirty pages
      have been sent to the translator, and this one still needs to write them
      to the backing storage
    <slpz> guillem: there's no problem if sync() returns before actually
      writting the changes to disk, but this also happens when shutting down
      the translator
    <slpz> guillem: in theory, locking mechanisms in libpager should prevent
      this from happening by keeping track of write operations, but this seems
      to fail in some situations

It helps a lot to run [[`syncfs --synchronous /`|hurd/syncfs]] before issuing
the `halt` or `reboot` command.  This will prevent most of the uncleanliness.
Of course, [[hurd/translator/ext2fs]] is meant to be doing this to-disk
synchronization internally upon translator shutdown, but evidently it doesn't
in all cases.

Apparently diskfs simply does not set filesystems as read-only:
<http://lists.gnu.org/archive/html/bug-hurd/2011-08/msg00024.html>.