TCP/IPv6 Migration Guide

Migration Considerations
HP NonStop TCP/IPv6 Migration Guide—524524-004
3-8
Platform
persistence manger $ZPM after a system load. You must add the TCP6MAN process
as a generic process to the NonStop Kernel subsystem to activate this feature.
Platform
NonStop TCP/IP runs on HP NonStop K-series servers, NonStop S-Series servers,
and Integrity NonStop servers; NonStop TCP/IPv6 runs on NonStop S-series servers
and Integrity NonStop servers.
Resource Management
With NonStop TCP/IPv6, processor utilization measurements of client applications may
tend to exhibit higher numbers than NonStop TCP/IP because the TCP/IP processing
is now being done in the context of the application. In the NonStop TCP/IP
environment, this work was attributed to the TCP/IP process.
From a system’s perspective, the overall processor utilization should be less since the
number of dispatches and context switches is minimized.
Retransmission Timer Enhancements
In NonStop TCP/IPv6, you can alter the following TCP retransmission variables on an
individual TCP socket basis by issuing a SETSOCKOPT socket library call from an
application:
•
Minimum TCP retransmission timeout. The minimum time allowed for a TCP
retransmission timer.
•
Maximum TCP retransmission timeout. The maximum time allowed for a TCP
retransmission timer.
•
Maximum TCP retransmission count. The maximum number of continuous
retransmissions prior to dropping a TCP connection.
•
Total TCP retransmission duration. The maximum continuous time spent
retransmitting without receiving an acknowledgement from the other end point.
See the TCP/IP Programming Manual for more information about using this feature
from an application.
You can also alter the time allowed for a TCP retransmission timer on a subsystem
level by using the SCF ALTER MON command. See the TCP/IPv6 Configuration and
Management Manual for more information about using this feature from SCF.
Note. TCP6SAM cannot be added as a generic process and therefore, even if TCP6MAN is
restarted automatically by the persistence manager, you still must start TCP6SAM processes
using interactive SCF or command files if you have applications that are using TCP6SAM as the
transport-service provider.