This RFC series adds logic to the Linux NFS server to make it wait a
few moments for clients to return a delegation before replying with
NFS4ERR_DELAY. There are two main benefits:
- This improves responsiveness when a delegated file is accessed
from another client
- This removes an unnecessary latency if a client has neglected to
return a delegation before attempting a RENAME or SETATTR
This series is incomplete:
- There are likely other operations that can benefit (eg. OPEN)
- The wait is a fixed 30ms delay; it would be better if the server
could match an incoming CB_RECALL reply with waiters so they can
proceed immediately, but I am still figuring out how that can be
done
Changes since RFC:
- Eliminate spurious console messages on the server
- Wait for DELEGRETURN for RENAME operations
- Add CB done tracepoints
- Rework the retry loop
---
Chuck Lever (3):
NFSD: Add tracepoints to report NFSv4 callback completions
NFSD: Make nfsd4_setattr() wait before returning NFS4ERR_DELAY
NFSD: Make nfsd4_rename() wait before returning NFS4ERR_DELAY
fs/nfsd/nfs4layouts.c | 2 +-
fs/nfsd/nfs4proc.c | 52 ++++++++++++++++++++++++++++++--------
fs/nfsd/nfs4state.c | 21 ++++++++++++++++
fs/nfsd/nfsd.h | 1 +
fs/nfsd/trace.h | 58 +++++++++++++++++++++++++++++++++++++++++++
fs/nfsd/xdr4.h | 2 ++
6 files changed, 124 insertions(+), 12 deletions(-)
--
Chuck Lever
