msgmnb(5)							File Formats Manual							 msgmnb(5)

NAME

       msgmnb - maximum number of bytes on a single System V IPC message queue

VALUES

   Default
   Failsafe
   Allowed Values
DESCRIPTION

       The  tunable  specifies	the maximum allowable total combined size, in bytes, of all messages queued in a single given System V IPC message
       queue at any one time.

       If a system call attempts to exceed the limit imposed by it will block (or return if was specified) until a caller of decreases the  number
       of bytes in the queue sufficiently such that the new message, along with other messages still on the queue, will fit within the limit.

       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 affect subsequent operations.

   When Should the Value of This Tunable Be Raised?
       Raise this tunable if applications have a need to store more data on a single queue.

   When Should the Value of This Tunable Be Lowered?
       Lower this tunable when applications have no need to store large amounts of data on a single queue.

   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,  when  the  tunable	is
       changed, adjustments may also be needed to the and tunables.

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

       msgrcv(2), msgsnd(2), mesg(5), msgmni(5), msgtql(5), msgmbs(5).

							     Tunable Kernel Parameters							 msgmnb(5)