Server User Manual

TABLE 5–1 Tuning 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 trac 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 buer.
tcp_recv_hiwat ndd /dev/tcp 8129 32768 Size of receive buer.
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 ecient, 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 eective at boot time.
Use the following command to get the current number of TCP connections.
netstat -nP tcp|wc -l
Tuning for the Solaris OS
Sun GlassFish Enterprise Server 2.1 Performance Tuning Guide • January 200996