Manage Shared Memory

In some cases, increasing the shared memory segment can lead to better network performance.

SAP Sybase IQ uses shared memory for two purposes:

When the client and server are installed on the same system, shared memory is the default communication mechanism, not TCP/IP.
When you specify the server command-line option -iqwmem, shared memory is used to provide wired memory.

If the -iqwmem option is used, increase the maximum shared memory segment size parameter in the /etc/system configuration file. Specify a configuration for the largest amount of wired memory you expect your system to support.

To create a shared segment to support a maximum physical memory of 3350MB for your system, for example, add the following line to the /etc/system file:

set shmsys:shminfo_shmmax=0xffffffff

Never set shmmax to a value greater than 7/8 of physical memory.

Local connections through shared memory are not supported for Sun Solaris x64 systems. Use standard network connectivity by adding the parameters -host <hostname> and -port <portnumber> to the client connection string.

Additional Information

Connection and Communication Parameters Reference > Network Communications Parameters
Utility Guide » start_iq Database Server Startup Utility » start_iq Server Options > -iqwmem iqsrv16 Server Option