Tuning for the Solaris OS

TABLE 5–1Tuning Parameters for Solaris

(Continued)

 

 

Parameter

Scope

 

Default

Tuned Value

Comments

 

 

 

 

 

tcp_conn_req_max_q

ndd /dev/tcp

128

1024

 

 

 

 

 

 

tcp_conn_req_max_q0

ndd /dev/tcp

1024

4096

 

 

 

 

 

 

tcp_ip_abort_interval

ndd /dev/tcp

480000

60000

 

 

 

 

 

 

tcp_keepalive_interval

ndd /dev/tcp

7200000

900000

For high traffic web sites, lower this

 

 

 

 

 

value.

 

 

 

 

 

tcp_rexmit_interval_initial

ndd /dev/tcp

3000

3000

If retransmission is greater than

 

 

 

 

 

30-40%, you should increase this

 

 

 

 

 

value.

 

 

 

 

 

tcp_rexmit_interval_max

ndd /dev/tcp

240000

10000

 

 

 

 

 

 

tcp_rexmit_interval_min

ndd /dev/tcp

200

3000

 

 

 

 

 

 

tcp_smallest_anon_port

ndd /dev/tcp

32768

1024

Set on clients too.

 

 

 

 

 

tcp_slow_start_initial

ndd /dev/tcp

1

2

Slightly faster transmission of small

 

 

 

 

 

amounts of data.

 

 

 

 

 

tcp_xmit_hiwat

ndd /dev/tcp

8129

32768

Size of transmit buffer.

 

 

 

 

 

tcp_recv_hiwat

ndd /dev/tcp

8129

32768

Size of receive buffer.

 

 

 

 

 

tcp_conn_hash_size

ndd /dev/tcp

512

8192

Size of connection hash table. See

 

 

 

 

 

“Sizing the Connection Hash Table”

 

 

 

 

 

on page 96.

 

 

 

 

 

 

Sizing the Connection Hash Table

The connection hash table keeps all the information for active TCP connections. Use the following command to get the size of the connection hash table:

ndd -get /dev/tcp tcp_conn_hash

This value does not limit the number of connections, but it can cause connection hashing to take longer. The default size is 512.

To make lookups more efficient, set the value to half of the number of concurrent TCP connections that are expected on the server. You can set this value only in /etc/system, and it becomes effective at boot time.

Use the following command to get the current number of TCP connections.

netstat -nP tcpwc -l

96

Sun GlassFish Enterprise Server 2.1 Performance Tuning Guide • January 2009

Page 96
Image 96
Sun Microsystems 820434310 manual Sizing the Connection Hash Table, Ndd -get /dev/tcp tcpconnhash, Netstat -nP tcpwc -l