kernel_optimize_test/fs/nfs/flexfilelayout
Trond Myklebust 260074cd84 pNFS/flexfiles: Add support for FF_FLAGS_NO_IO_THRU_MDS
For loosely coupled pNFS/flexfiles systems, there is often no advantage
at all in going through the MDS for I/O, since the MDS is subject to
the same limitations as all other clients when talking to DSes. If a
DS is unresponsive, I/O through the MDS will fail.

For such systems, the only scalable solution is to have the pNFS clients
retry doing pNFS, and so the protocol now provides a flag that allows
the pNFS server to signal this.

If LAYOUTGET returns FF_FLAGS_NO_IO_THRU_MDS, then we should assume that
the MDS wants the client to retry using these devices, even if they were
previously marked as being unavailable. To do so, we add a helper,
ff_layout_mark_devices_valid() that will be called from layoutget.

Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2015-11-02 13:50:37 -05:00
..
flexfilelayout.c pNFS/flexfiles: Add support for FF_FLAGS_NO_IO_THRU_MDS 2015-11-02 13:50:37 -05:00
flexfilelayout.h pNFS/flexfiles: Add support for FF_FLAGS_NO_IO_THRU_MDS 2015-11-02 13:50:37 -05:00
flexfilelayoutdev.c NFSv4.1/flexfiles: Mark layout for return if the mirrors are invalid 2015-09-01 15:12:11 -07:00
Makefile pnfs/flexfiles: Add the FlexFile Layout Driver 2015-02-03 11:06:52 -08:00