diff options
Diffstat (limited to 'doc/cephfs/lazyio.rst')
| -rw-r--r-- | doc/cephfs/lazyio.rst | 23 |
1 files changed, 23 insertions, 0 deletions
diff --git a/doc/cephfs/lazyio.rst b/doc/cephfs/lazyio.rst new file mode 100644 index 00000000..6737932a --- /dev/null +++ b/doc/cephfs/lazyio.rst @@ -0,0 +1,23 @@ +====== +LazyIO +====== + +LazyIO relaxes POSIX semantics. Buffered reads/writes are allowed even when a +file is opened by multiple applications on multiple clients. Applications are +responsible for managing cache coherency themselves. + +Libcephfs supports LazyIO since nautilus release. + +Enable LazyIO +============= + +LazyIO can be enabled by following ways. + +- ``client_force_lazyio`` option enables LAZY_IO globally for libcephfs and + ceph-fuse mount. + +- ``ceph_lazyio(...)`` and ``ceph_ll_lazyio(...)`` enable LAZY_IO for file handle + in libcephfs. + +- ``ioctl(fd, CEPH_IOC_LAZYIO, 1UL)`` enables LAZY_IO for file handle in + ceph-fuse mount. |