nfs3_jukebox_delay.5 (2010 09)

n
nfs3_jukebox_delay(5) nfs3_jukebox_delay(5)
(Tunable Kernel Parameters)
NAME
nfs3_jukebox_delay - control the length of time the NFS version 3 client waits before re-transmitting a
request after receiving a NFS3ERR_JUKEBOX error
VALUES
Failsafe
1000
Default
1000
Allowed values
Minimum: 100, which is approximately one second
Maximum:
MAXINT
Recommended values
A warning will be issued at runtime if the tunable is set to a value less then 100 hundredths of a second
or greater than 60000 hundredths of a second since this is outside the tested limits. This is not a serious
warning but just an information message for the administrator.
DESCRIPTION
nfs3_jukebox_delay
controls the duration of time that the NFS version 3 client waits to transmit a
new request after receiving the error
NFS3ERR_JUKEBOX
from a previous request. The error,
NFS3ERR_JUKEBOX, is generally returned from the server when the file is temporarily unavailable for
some reason. These situations are generally associated with hierarchical storage and CD or tape
jukeboxes.
Who Is Expected to Change This Tunable?
The distributed file system administrator should examine this value depending on the speed of the
storage on the NFS file server.
Restrictions on Changing
The
nfs3_jukebox_delay
tunable is dynamic; tuning will take effect immediately on the running sys-
tem.
When Should the Value of This Tunable Be Raised?
The value should be increased if there are long delays in making the file available. This will reduce net-
work overhead due to repeated retransmissions.
What Are the Side Effects of Raising the Value?
Increasing the delay before retransmission will impact performance if the file unavailability is shorter
than the increased delay.
When Should the Value of This Tunable Be Lowered?
If the time the file is unavailable is small, then decreasing this value should not impact performance.
What Are the Side Effects of Lowering the Value?
If the time the file is unavailable is large, then there will be an increase in network overhead.
WARNINGS
All HP-UX kernel tunable parameters are release specific. This parameter may be removed or have its
meaning changed in future releases of HP-UX.
Installation of optional kernel software, from HP or other vendors, may cause changes to tunable parame-
ter values. After installation, some tunable parameters may no longer be at the default or recommended
values. For information about the effects of installation on tunable values, consult the documentation for
the kernel software being installed. For information about optional kernel software that was factory
installed on your system, see HP-UX Release Notes at
http://www.hp.com/go/hpux-core-docs.
AUTHOR
nfs3_jukebox_delay was developed by Sun Microsystems, Inc.
HP-UX 11i Version 3: September 2010 1 Hewlett-Packard Company 1

Summary of content (2 pages)