dbsrv16  -gnh integer ...

Four times the -gn database server option value

All operating systems except Windows Mobile.

Network database server (dbsrv16) only.

This option sets the maximum multiprogramming level of the network database server. It limits the maximum number of tasks (both user and system requests) that the network database server can execute concurrently. If the network database server receives an additional request while at this limit, the new request must wait until an executing task completes. The number of active tasks that can execute simultaneously depends on the number of network database server threads and the number of logical processors in use.

The maximum number of combined unscheduled and active requests is limited by the -gm network database server option, which limits the number of connections to the network database server.

Setting the -gnh value too high can result in errors because a larger portion of the system's address space is consumed for stack space.

The network database server's kernel uses tasks as the scheduling unit. The execution of any user request requires at least one task. However, a request may cause the scheduling of additional tasks on its behalf. One example of this behavior is if the request involves the execution of an external procedure or function (Java, Perl, CLR, and so on) that in turn makes database requests back into the network database server.

When intra-query parallelism is involved, each access plan component executed in parallel is a task. These tasks count toward the -gnh limit as though they were separate requests. However, tasks created for intra-query parallelism are not reflected in the database properties that track the number of active and inactive requests.

• SQL Anywhere threading
• Database server configuration of the multiprogramming level
• MaxMultiProgrammingLevel server property
• max_query_tasks option
• -gn database server option
• -gna database server option
• -gnl database server option
• -gss database server option
• sa_server_option system procedure