lockd
Daemon
The lockd
daemon supports record-locking operations on NFS files. The
lockd
daemon manages RPC connections between the client and the server
for the Network Lock Manager (NLM) protocol. The daemon is normally started without any
options. You can use three options with this command. You can set these options either from
the command line or by setting parameters using the sharectl
command. For
more information, see the
lockd
(8) man page.
Note:
TheLOCKD_GRACE_PERIOD
keyword and the -g
option have been deprecated. The deprecated keyword is replaced with the new
grace_period
parameter. If both keywords are set, the value for
grace_period
overrides the value for
LOCKD_GRACE_PERIOD
.
Like LOCKD_GRACE_PERIOD
, the
grace_period
=graceperiod parameter sets the
number of seconds after a server reboot that the clients have to reclaim both NFS Version 3
locks, provided by NLM, and NFS Version 4 locks.
The
lockd_retransmit_timeout
=timeout parameter
selects the number of seconds to wait before retransmitting a lock request to the remote
server. This option affects the NFS client-side service. The default value for
timeout is 5 seconds. Decreasing the
timeout value can improve response time for NFS clients on a
"noisy" network. However, this change can cause additional server load by
increasing the frequency of lock requests. The same parameter can be used from the command
line by starting the daemon with the -t
timeout option.
The lockd_servers
=number parameter
specifies the maximum number of concurrent lockd
requests. The default
value is 1024.
The nthreads
parameter specifies the maximum number of concurrent
threads that the server can handle. All NFS clients that use UDP share a single connection
with the NFS server. Under these conditions, you might have to increase the number of
threads that are available for the UDP connection. A minimum calculation would be to allow
two threads for each UDP client. However, this number is specific to the workload on the
client, so two threads per client might not be sufficient. The disadvantage to using more
threads is that when the threads are used, more memory is used on the NFS server. If the
threads are never used, however, increasing nthreads has no
effect. The same parameter can be used from the command line by starting the daemon with the
nthreads
option.