NAME
dump_concurrent_on — enable or disable option for system to dump memory using multiple dump units when a kernel panic occurs on Integrity systems
VALUES
Allowed values
0 disable multiple dump units (concurrency off)
1 enable multiple dump units (concurrency on)
Recommended value
1 allow the kernel to choose whether or not to dump concurrently
DESCRIPTION
On large systems, the time required to dump system memory when a kernel
panic occurs can be excessive or even prohibitive, depending on how much
physical memory is installed in the system.
Concurrent dump capability results in faster dumps by dividing the
task to different dump units which can execute in parallel.
The default value for
dump_concurrent_on
is
1.
The system determines whether or not to dump with multiple units
based on the resources (CPUs and disks) available on the system and the
properties of the drivers.
The
crashconf
command may also be used to specify whether or not to use multiple
dump units.
It stores this information in its configuration file
/etc/rc.config.d/crashconf.
Who Is Expected to Change This Tunable?
Only HP Field Engineers should change the value of this tunable.
Restrictions on Changing
Changes to this tunable take effect immediately.
When Should the Tunable Be Turned On?
This tunable should be turned on to allow dumps to dump with
multiple dump units when there is a system crash if there are sufficient
resources.
What Are the Side Effects of Turning the Tunable Off?
Dumps may take more time.
When Should the Tunable Be Turned Off?
The tunable should be turned off if there is a problem using
multiple dump units.
What Are the Side Effects of Turning the Tunable On?
The system decides whether or not to use multiple dump units
based on the resources available.
What Other Tunables Should Be Changed at the Same Time?
None.
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 parameter 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://docs.hp.com.
AUTHOR
dump_concurrent_on
was developed by HP.
Printable version
