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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)

Check Out this Related Man Page

semvmx(5)							File Formats Manual							 semvmx(5)

NAME

       semvmx - maximum value of any single System V IPC semaphore

VALUES

   Failsafe
   Default
   Allowed values
DESCRIPTION

       The tunable specifies the maximum value any given System V IPC semaphore can have.

       If an application attempt to exceed this limit, it will receive an error from or 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.

   Restrictions on Changing
       Changes to this tunable take effect at the next reboot.

       Note:  If the DynSysVSem optional product bundle is installed increases in the tunable value take effect immediately; decreases in the tun-
       able value take effect at the next reboot.

   When Should the Value of This Tunable Be Raised?
       If an application requires larger semaphore values.

   When Should the Value of This Tunable Be Lowered?
       If requirements for the single semaphore value has decreased, or if there for limit protection on run-away applications which change  sema-
       phores.

   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 Consider changes to when changing

       Note:  If the DynSysVSem optional product bundle is installed then the and tunables are ignored and have no effect.

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

       semop(2), semctl(2), sema(5), semaem(5), semmni(5), semmns(5), semmnu(5), semmsl(5), semume(5), sysv_hash_locks(5).

							     Tunable Kernel Parameters							 semvmx(5)
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