semmsl(5) [hpux man page]

semmsl(5)							File Formats Manual							 semmsl(5)

NAME

       semmsl - maximum number of System V IPC semaphores per identifier

VALUES

   Failsafe
   Default
   Allowed values
DESCRIPTION

       The tunable specifies the maximum number of individual System V IPC semaphores per semaphore identifier (ID).

       If an application attempts to exceed this limit, it will receive an error from

       For more information about System V semaphores, refer to the section of the sema(5) manpage.

   Who Is Expected to Change This Tunable?
       Anyone.

   When Should the Value of This Tunable Be Raised?
       If applications require a larger number of semaphores per ID.

   When Should the Value of This Tunable Be Lowered?
       If application requirements for semaphores per ID has decreased or there is a need to protect against ill-behaved applications.

   What Other Tunable Values Should Be Changed at the Same Time?
       All the System V semaphore tunables are interrelated and should not be treated as independent variables.  The tunables must be evaluated as
       a system to ensure they reflect the application requirements.  The semaphore tunables include and Specifically, a change in the tunable may
       require a change in the tunable.

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.

       Prior to HP-UX 11i Version 1 the maximum number of semaphores per ID was an undocumented constant 2048 in the header file Typically  appli-
       cations	do not depend upon this limitation.  For those that were compiled with the old constant, tunable values higher than 2048 will gen-
       erally not be a problem.  However, tunable values lower than 2048 may cause other such applications to fail.  These should  be  recoded	to
       obtain the current value from pstat_getipc(2).

       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 AT&T.

SEE ALSO

       semget(2), sema(5), semaem(5), semmns(5), semmni(5), semmnu(5), semume(5), semvmx(5), sysv_hash_locks(5).

							     Tunable Kernel Parameters							 semmsl(5)

msgmni(5)							File Formats Manual							 msgmni(5)

NAME

       msgmni - maximum number of system-wide System V IPC message queues (IDs) allowed

VALUES

   Default
   Failsafe
   Allowed Values
DESCRIPTION

       The tunable specifies the maximum number of system-wide System V IPC message queue identifiers (one per queue).	Each message queue created
       has an identifier (ID) and there is an upper limit of identifiers.

       Applications use the system call to create new queues.  If all IDs have been used, will return

       If a process acquires a message queue, but the process terminates without removing it, the queue and all its  messages  remain.	 Abandoned
       message queues can be removed with the command.	Message queue status can be monitored using the command.

       For more information about System V message queues, refer to the section of the mesg(5) manpage.

   Who Is Expected to Change This Tunable?
       Anyone.

   Restrictions on Changing
       This tunable is dynamic.  Changes to to this tunable take effect immediately.

   When Should the Value of This Tunable Be Raised?
       Raise this tunable when applications require more queues.

   When Should the Value of This Tunable Be Lowered?
       Lower this tunable when the requirement for queues has diminished.

   What are the Side Effects of Lowering the Value?
       Lowering  the value increases the risk of application failure due to the inability to create more message queues.  Lowering the tunable has
       no effect on any active message queues, even if the new tunable value is less than the number of queues created in the system. However,	no
       new queues may be created until the number of active queues falls below the setting of

   What Other Tunable Values Should Be Changed at the Same Time?
       All  the  System  V message queue tunables are interrelated and should be treated as independent variables.  The set must be evaluated as a
       system to ensure the tunables reflect the application requirements.  The message tunables include and Specifically, and tunables  may  need
       adjustment along with changes to the tunable.

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 AT&T.

SEE ALSO

       ipcrm(1), ipcs(1), msgget(2), mesg(5), msgmnb(5), msgtql(5), msgmbs(5).

							     Tunable Kernel Parameters							 msgmni(5)