NS3000/iX Operations and Maintenance Reference Manual (36922-90042)

Chapter 7 157
Commands
NSCONTROL SERVER
There is no simple formula for determining how many precreated
servers to specify. Since each precreated server consumes one set of
process resources, including process related system table entries and
virtual memory for stack space, the number chosen must be a tradeoff
between using system resources and allowing fast service response. The
node manager needs to estimate, on the average, the number of
concurrent users of each type of server. This number is used for the
minimum number of servers of each type. Since the DSSERVER process is
used by several services, and some of these services are active for a long
time, it makes sense to allocate a larger number of DSSERVER servers
than NFT, VTSERVER, LOOPBACK or NSSTATUS servers.
An alternative to allocating a greater number of DSSERVER servers is to
allocate the program files NFT.NET.SYS, VTSERVER.NET.SYS,
DSSERVER.NET.SYS, LOOPBACK.NET.SYS, and NSSTATUS.NET.SYS. This
alternative is most advantageous for DSSERVER, where the allocation of
the program file is a significant portion of the set up time. The NFT
server must read keywords and messages from the NFTCAT2 catalog as
well as allocate the program file when the server is created, so the
performance gain is not as great as for DSSERVER.
Creating reserved servers or using the allocation alternative means
that the program file is in use, just as when a program is run. Since the
program file is in use, it cannot be purged, replaced, or backed up.
Before any software installation, when the program files are replaced or
backed up, check that the program files are not allocated and that there
are no reserved servers.
Example
The following command sets the minimum number of DSSERVER
processes to five and the maximum to 10. Five reserved DSSERVER
processes are created immediately and are available for future change
requests. The minimum number of servers, which includes both
reserved and active servers, is restricted to five. When an active server
is returned to the reserved pool, if there are already five reserved
servers, the extra server is terminated. The maximum limit means that
if there are 10 DSSERVER processes active, any new change requests will
be rejected.
:NSCONTROL SERVER=DSSERVER,5,10