EMS Manual

Configuring EMS
EMS Manual—426909-005
12-21
Installation and System Generation Considerations
Installation and System Generation
Considerations
Only a few EMS components have operating characteristics you must consider during
system generation: the primary collector, the compatibility distributor (optionally), and
the template files. Other components such as code files and definition files only need
to be copied to a convenient location. For more information about EMS system
generation, see the System Generation Manual.
The Primary Collector
Exactly one primary collector process is required on each system (node). The primary
collector is always installed during the SYSGEN phase of the INSTALL process, and is
always named $0. The INSTALL process includes the file $ISV.ZEMS.OPCOLL in the
SYSGEN auxiliary file, CONFAUX.
During system generation, a buffer is allocated to $0 for queuing event messages on
their way to the collector log and for holding filters, including one burst filter.
G-Series RVU Considerations
In systems running a G-series RVU of the NonStop Kernel, you cannot configure the
number of pages (XPOOLPAGES) that $0 uses for buffer space. $0 allocates the
maximum number of pages, 128, so you do not need to reconfigure XPOOLPAGES.
D-Series RVU Considerations
In systems running a D-series RVU of the NonStop Kernel, this buffer has 50 pages of
resident extended memory, which is big enough for most systems but might be too
small for some. For an explanation why the collector buffer could prove too small, and
for some remedies, see Logging Integrity
on page 12-17. An obvious remedy—the only
one that directly involves the primary collector—is to enlarge the buffer, but you can
only do this during SYSGEN. If you can foresee a need for more than 50 pages in the
buffer, enlarge it when you install the collector.
Once the primary collector is running, to find out if the buffer is too small, look at the
EMSCINFO status display. (See Example 13-1
on page 13-18.) The Buffer Failures
field (right side, lower center) shows the number of event messages that $0 could not
accept because the buffer was full. To enlarge it requires another system generation.
To change the buffer size, change the value of the XPOOLPAGES parameter in the
SYSTEM_PROCESS_MODIFIERS paragraph of the configuration file. This optional
paragraph can include the XPOOLPAGES parameter and EMSFLAGS. (See The
Compatibility Distributor ($Z0) on page 12-22.) The paragraph looks like:
SYSTEM_PROCESS_MODIFIERS:
$0 XPOOLPAGES n,
EMSFLAGS b;