This patch applies on top of the [PATCH Version 3 00/11] NFSv4.1 file layout data server quick failover patchset. -->Andy On Apr 4, 2012, at 4:22 PM, <andros@xxxxxxxxxx> wrote: > From: Andy Adamson <andros@xxxxxxxxxx> > >> From patch comments: > > The "invalid layout" class of errors is handled by destroying the layout and > getting a new layout from the server. Currently, the layout must be > destroyed before a new layout can be obtained. > > This means that all references (e.g.lsegs) to the "to be destroyed" layout > header must be dropped before it can be destroyed. This in turn means waiting > for all in flight RPC's using the old layout as well as draining the data > server session slot table wait queue. > > Set the NFS_LAYOUT_INVALID flag to redirect I/O to the MDS while waiting for > the old layout to be destroyed. > > Testing: > > Tested against a modified pynfs filelayout server with one DS. I mount the DS, > set an NFS4ERR_BADHANDLE error in config/ops/write file which triggers the > error on the "first" write. Umount the DS. Mount the MDS and run > "dd if=/dev/zero of=/mnt/dd.out bs=4096 count=200". This results in a maxreqs > worth of writes to the DS (8 for pynfs) before the NFS4ERR_BADHANDLE gets > sent whereon writes are redirected to the MDS. Once the DS on the wire RPC's > have all returned, and all the DS slot_tbl_waitq tasks are redirected to the > MDS, the layout is destroyed, a new layout is obtained, and the writes return > to pNFS before the 'dd' command finishes. > > Andy Adamson (1): > NFSv4.1 resend LAYOUTGET on data server invalid layout errors > > fs/nfs/nfs4filelayout.c | 27 +++++++++++++++++++++++---- > fs/nfs/nfs4filelayout.h | 13 +++++++++++++ > fs/nfs/pnfs.c | 1 + > fs/nfs/pnfs.h | 1 + > 4 files changed, 38 insertions(+), 4 deletions(-) > > -- > 1.7.6.4 > -- To unsubscribe from this list: send the line "unsubscribe linux-nfs" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
