mirror of
https://github.com/ceph/ceph
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8ebd0fb74a
Fixes: http://tracker.ceph.com/issues/38729 Signed-off-by: "Yan, Zheng" <zyan@redhat.com>
24 lines
642 B
ReStructuredText
24 lines
642 B
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======
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LazyIO
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======
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LazyIO relaxes POSIX semantics. Buffered reads/writes are allowed even when a
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file is opened by multiple applications on multiple clients. Applications are
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responsible for managing cache coherency themselves.
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Libcephfs supports LazyIO since nautilus release.
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Enable LazyIO
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=============
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LazyIO can be enabled by following ways.
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- ``client_force_lazyio`` option enables LAZY_IO globally for libcephfs and
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ceph-fuse mount.
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- ``ceph_lazyio(...)`` and ``ceph_ll_lazyio(...)`` enable LAZY_IO for file handle
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in libcephfs.
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- ``ioctl(fd, CEPH_IOC_LAZYIO, 1UL)`` enables LAZY_IO for file handle in
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ceph-fuse mount.
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