Technical data

1.3 Using Online Help ........................................... 1–30
1.4 Using OpenVMS ANALYZE Extensions ........................... 1–31
2 Tuning Techniques
2.1 Subsystem Attributes ......................................... 2–1
2.1.1 Displaying Subsystems and Attributes ........................ 2–1
2.1.1.1 Static and Dynamic Subsystems .......................... 2–2
2.1.1.2 Displaying the Attribute Values for a Subsystem . . . ........... 2–3
2.1.2 Modifying Subsystem Attribute Values ........................ 2–4
2.1.2.1 Reconfiguring Attributes ................................ 2–4
2.1.3 Configuring Attributes . .................................... 2–4
2.1.3.1 Format of the SYSCONFIGTAB File ....................... 2–5
2.1.3.2 Stanza File Format .................................... 2–6
2.1.4 Modifying Kernel Subsystems . . . ............................ 2–7
2.1.5 Modifying Socket Subsystem Attributes ........................ 2–8
2.1.5.1 Increasing the Maximum Number of Pending TCP
Connections .......................................... 2–8
2.1.5.2 Increasing the Minimum Number of Pending TCP Connections . . . 2–8
2.1.5.3 Increasing the Maximum Size of a Socket Buffer . . . ........... 2–9
2.1.6 Modifying Internet Subsystem Attributes . . . ................... 2–9
2.1.6.1 Increasing the Size of a TCP Hash Table . ................... 2–9
2.1.6.2 Increasing the Number of TCP Hash Tables ................. 2–10
2.1.6.3 Increasing the Size of the Kernel Interface Alias Table ......... 2–10
2.1.6.4 Increasing the TCP Partial Connection Timeout Rate .......... 2–11
2.1.6.5 Slowing TCP Retransmission Rate ......................... 2–11
2.1.6.6 Enabling the TCP Keepalive Function . . . ................... 2–12
2.1.6.7 Increasing the Timeout Rate for TCP Connection Context ....... 2–13
2.1.6.8 Disabling Delayed Acknowledgment ....................... 2–13
2.1.6.9 Modifying the Range of Outgoing Connection Ports . ........... 2–14
2.1.6.10 Disabling Use of the PMTU Protocol ....................... 2–14
2.1.7 Displaying Socket Statistics ................................. 2–15
2.2 Tuning Server Applications .................................... 2–15
2.2.1 Configuring Memory for High Performance . . ................... 2–15
2.2.2 Logging IP Addresses . . .................................... 2–16
2.2.3 Increasing the Auxiliary Server Connection Limit ................ 2–16
2.2.4 Increasing the Maximum Number of BG Devices ................ 2–16
2.3 Solving Performance Problems .................................. 2–17
2.3.1 Tuning Recommendations for a Primary Server .................. 2–18
2.3.2 Improving Gigabit Ethernet Performance . . . ................... 2–18
A Troubleshooting Utilities Reference
arp....................................................... A–2
dig ....................................................... A–5
ifconfig .................................................... A–11
ndc....................................................... A–16
netstat .................................................... A–18
nslookup ................................................... A–22
ping . . .................................................... A–27
route . .................................................... A–31
sysconfig ................................................... A–35
sysconfigdb ................................................. A–39
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