On Mon, Feb 01, 2016 at 12:21:04PM -0500, Trond Myklebust wrote: > The following patchset is intended as an RFC to demonstrate how we could > implement multipathing in NFS. > It adds basic support for attaching multiple RPC transports to a client, > an embryonic policy mechanism for switching tasks across those transports > (with a round-robin policy implementation), as well as helpers to allow > iteration of tasks across all tranports (for instance in order to > support NFSv4.1's BIND_CONN_TO_SESSION). > > A lot of polish and finishing touches are missing. For instance, I have yet > to add support in debugfs for these transports, and there is no support > for mounting with NFSv4.1 session trunking. However there is a demonstrator > that implements pNFS multipathing over NFSv3. Adding support for NFSv4.1 > requires that you call EXCHANGE_ID to allow verification of the > major/minor server and scopeid fields, which should not be too hard. > > More to come, but in the meantime, comments are welcome... Since your prototype is doing round-robin per task, I assume the motivating problem is that you don't want to waste bandwidth when there's multiple links available. Is that right, or is there some other goal you have in mind? --b. > > Cheers > Trond > > -------------- > v2 & v3: Fix up kbuild warnings > > Trond Myklebust (13): > SUNRPC: Remove unused function rpc_task_reset_client > SUNRPC: Reorder rpc_task to put waitqueue related info in same > cachelines > SUNRPC: Uninline xprt_get(); It isn't performance critical. > SUNRPC: Make freeing of struct xprt rcu-safe > SUNRPC: Add a structure to track multiple transports > SUNRPC: Make rpc_clnt store the multipath iterators > SUNRPC: Use the multipath iterator to assign a transport to each task > SUNRPC: Allow caller to specify the transport to use > SUNRPC: Add a helper to apply a function to all the rpc_clnt's > transports > SUNRPC: Make NFS swap work with multipath > NFSv4.1: nfs4_proc_bind_conn_to_session must iterate over all > connections > SUNRPC: Allow addition of new transports to a struct rpc_clnt > pnfs/NFSv4.1: Add multipath capabilities to pNFS flexfiles servers > over NFSv3 > > fs/nfs/nfs4proc.c | 51 +++- > fs/nfs/pnfs_nfs.c | 16 +- > include/linux/sunrpc/clnt.h | 18 +- > include/linux/sunrpc/sched.h | 32 +-- > include/linux/sunrpc/xprt.h | 22 +- > include/linux/sunrpc/xprtmultipath.h | 69 +++++ > net/sunrpc/Makefile | 3 +- > net/sunrpc/auth_gss/auth_gss.c | 4 +- > net/sunrpc/clnt.c | 326 ++++++++++++++++++------ > net/sunrpc/rpcb_clnt.c | 10 +- > net/sunrpc/sched.c | 2 + > net/sunrpc/xprt.c | 42 ++-- > net/sunrpc/xprtmultipath.c | 473 +++++++++++++++++++++++++++++++++++ > net/sunrpc/xprtsock.c | 4 +- > 14 files changed, 938 insertions(+), 134 deletions(-) > create mode 100644 include/linux/sunrpc/xprtmultipath.h > create mode 100644 net/sunrpc/xprtmultipath.c > > -- > 2.5.0 > > -- > 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 -- 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
