04-06-2011
If all available CPU isn't being used that generally means the process is waiting for I/O, and "assigning more CPU" to a sleeping process is pretty pointless.
Perhaps your kernel module is having trouble keeping up with the userspace code? What are you actually doing anyway?
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LEARN ABOUT HPUX
core_addshmem_read
core_addshmem_read(5) File Formats Manual core_addshmem_read(5)
NAME
core_addshmem_read - determines the inclusion of readable shared memory in a process core dump
VALUES
Failsafe
Default
Allowed values
or
DESCRIPTION
The tunable was added in response to a problem where a customer was limited in debugging a user-level process crash because shared memory
segments were not written as part of the core file.
Upon core dump, the sections of user memory labeled as shared read-only are written (along with the normal data sections) if this tunable
is set to and left out if it is set to
Who is Expected to Change This Tunable?
Anyone.
Restrictions on Changing
Changes to this tunable take effect immediately.
When Should the Value of This Tunable Be Raised?
When you wish to include read-only shared memory segments in user core files due to debugging needs by developers or maintainers on the
system.
What Are the Side Effects of Raising the Value?
User process core files would increase in most cases (most applications use at least some shared memory). This could be a problem on sys-
tems where disk space is at a premium.
When Should the Value of This Tunable Be Lowered?
When there is no need for debugging core files where shared memory corruption or data values are in question.
What Are the Side Effects of Lowering the Value?
Core files will tend to be smaller.
What Other Tunable Values Should Be Changed at the Same Time?
Certainly think about which does the same thing for read/write shared memory segments.
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 tun-
able values, consult the documentation for the kernel software being installed. For information about optional kernel software that was
factory installed on your system, see at
AUTHOR
was developed by HP.
Tunable Kernel Parameters core_addshmem_read(5)