Managing NFS and KRPC Kernel Configurations in HP-UX 11i v2 (November 2013)

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2.4 KRPC Server Tunables
Table 2.4-1 lists the KRPC server tunables. The last column specifies which NFS patch first introduced
the tunable.
Table 2.4-1 KRPC Server Tunables
Kctune Tunable Name
Range
Default Value
Units
Patch ID
rpc_svc_cltsmaxdupreqs
1 to 2
31
-1
1024
Requests
PHNE_33981
rpc_svc_cotsmaxdupreqs
1 to 2
31
-1
1024
Requests
PHNE_33981
rpc_svc_idle_timeout
1 to 2
31
-1
360000
Milliseconds
PHNE_33981
rpc_svc_ippktinfo_opt*
0 to 1
0
Boolean
PHNE_37487
rpc_svc_maxthreads*
1 to 2
31
-1
10
Threads
PHNE_33981
rpc_svc_nfs_cpu_bind_method*
0 to 1
0
Boolean
PHNE_34549
* This tunable is obsolete after the HP-UX 11i v2 release.
2.4.1 rpc_svc_cltsmaxdupreqs
Description
The rpc_svc_cltsmaxdupreqs tunable controls the size of the duplicate request cache, which detects
RPC level retransmissions on connectionless transports such as UDP. This cache avoids processing of
retransmitted requests that might be non-indempotent.
Tested values
Default: 1024
Min: 1
Max: 2048
Note: If the tunable is set to a value greater than 2048, an
informational warning is issued at runtime. This value is
outside the tested limits.
Restrictions on changing
The rpc_svc_cltsmaxdupreqs tunable is dynamic. System reboot is not required to activate changes
made to this tunable. However, if the cache is full, decreasing the current value has no effect until the
system is rebooted.
Modifying the value
Increasing the value of this tunable to a value higher than the default can result in longer search times
to find entries in the cache. These longer search times can affect the performance of the NFS server. If
a non-idempotent request is mistakenly serviced twice by the NFS server, decreasing the value of this
tunable can trigger false failures on the NFS client side. For example, if an attempt to create a
directory returns a status of failed but the directory is actually created, the retransmitted MKDIR
request was not detected by the server. HP recommends leaving the rpc_svc_cltsmaxdupreqs tunable
set to the default value unless you have been explicitly instructed to change it by HP Support.