Pathway/XM System Management Manual

Managing a Pathway/XM Environment
Compaq NonStop™ Pathway/XM System Management Manual—426761-001
7-26
LINKMON Processes
For all systems that have the NonStop
TM
TS/MP product installed, a LINKMON
process is included by default in the system image for each CPU. A LINKMON process
starts in each CPU as the CPU is loaded.
Process Names
LINKMON process names appear in PXMCOM displays in the form
L\system.$ZLnn, where nn is the number of the CPU on which the LINKMON
process resides. PXMCOM adds an “L” before the system name to indicate that it is a
LINKMON process, for example:
L\ABC.$ZL05
Initialization
The LINKMON process in a CPU does not initialize itself until a requester in that CPU
calls the Pathsend SERVERCLASS_SEND_ procedure. Successful initialization of the
LINKMON process results in a message to the system log, $0. For example, if the
LINKMON process in CPU 1 is successfully initialized, it logs the following message:
LINKMON ($ZL01) - Initialized and running
Once initialized, a LINKMON process executes until the CPU halts or is reset.
If the LINKMON process initialization fails, the LINKMON process performs the
following:
•
Returns an error to the application (Pathsend error 947, file system error 43).
•
Logs one or more messages to the system log.
•
Returns to its original state and waits 10 seconds before processing additional
Pathsend procedure calls, so that subsequent sends to the uninitialized LINKMON
process do not flood $0.
When the LINKMON process receives the next server-class send call, it tries again to
initialize itself.
Limits
During initialization, a LINKMON process allocates extended memory sufficient to
support the maximum number of:
•
PATHMON processes with which a LINKMON process can communicate
•
Server classes to which a LINKMON process can have outstanding links across all
PATHMON processes
•
Concurrent links to server processes across all PATHMON processes, per
LINKMON process
•
Concurrent, outstanding server-class send operations, per LINKMON process
(A server-class send operation is outstanding until the LINKMON process has
replied to the Pathsend process.)