core_addshmem_write(5)core_addshmem_write(5)NAMEcore_addshmem_write - determines the inclusion of read/write shared
memory in process core dump
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-
write 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?
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-write shared memory segments in user core
files due to debugging needs by developers or maintainers on the sys‐
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 systems
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 cor‐
ruption 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-only shared
All HP-UX kernel tunable parameters are release specific. This parame‐
ter may be removed or have its meaning changed in future releases of
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 val‐
ues. For information about the effects of installation on tunable val‐
ues, consult the documentation for the kernel software being installed.
For information about optional kernel software that was factory
installed on your system, see at
was developed by HP.
Tunable Kernel Parameters core_addshmem_write(5)