tcp_hashtablesz

Description

This parameter controls the size of the TCP hash table.

Value

Default: 0 (Auto-configure)

Range: 64-8192

When to Change

This parameter should not normally need to be changed, but might be changed in order to reduce the consumption of system RAM on systems that are not used to handle large numbers of networking applications, or to increase the number of hash buckets on systems that primarily provide networking services.

Using a zero value specifies that the table is to be sized based on system RAM. A non-zero value specifies the number of hash buckets to use for TCP. The system automatically adjusts this number to support the requirements of the hashing algorithm. For example, entering a value of 512 will create 1025 buckets, since TCP uses the extra space for processing connections in the TIME-WAIT state.

Restrictions

The system silently enforces a minimum value of 64 hash buckets and a maximum value of 8192 hash buckets.