Read will get the newest content. If the read arrives during the write interval, it will wait for the write applied. On Wed, Jul 23, 2014 at 10:22 AM, James Pan <devjmp at yahoo.com> wrote: > Hi everyone, > > I am reading the FileStore source code and confused with the read() and write() process. > > If journal is enable, write() will be acknowledged after the changes are committed to the journal device but before they are applied to the file system. However read() is always satisfied from the OSD file on the file system, so if a read arrives during this interval. Will the read get the stale data? Does this behavior break the read-after-write posix semantics? Shouldn't the read go to the journal for the latest data? > > Please point me out if my understanding is incorrect, thanks very much. > > Best regards, > James Pan > > _______________________________________________ > ceph-users mailing list > ceph-users at lists.ceph.com > http://lists.ceph.com/listinfo.cgi/ceph-users-ceph.com -- Best Regards, Wheat
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