Timeout options

The high-speed connector provides the API, synchronous, and group connect timeouts to control message exchange between the server and z/TPF applications.

API timeout
Specifies the maximum amount of time that an application can wait for a request to be sent and the response to be received after the application calls a tpf_send_message, tpf_send_async_message, tpf_httpSendRequest, or tpf_httpSendAsyncRequest function. The API timeout is specified on the tpf_send_message, tpf_send_async_message, tpf_httpSendRequest, and tpf_httpSendAsyncRequest function. The API timeout includes the amount of time that is needed to establish sessions. You must consider the time that is needed to establish sessions when you determine the timeout on the API.
Synchronous timeout
Specifies the maximum amount of time that an application can wait to complete sending a request to a particular endpoint before sending the request to a different endpoint in the same endpoint group. The high-speed connector tries to send the request to another endpoint in the same endpoint group under one of the following conditions:
  • The high-speed connector is not expecting a response and the time expires before the send is completed.
  • The high-speed connector is expecting a response and the time expires before the high-speed connector sends the request and reads the response.
The synchronous timeout value is specified in the endpoint group descriptor file with the <syncTimeout> element.

If the tpf_send_async_message is called and the TPF_HSC_KEEP_REQUEST option is not set or the tpf_httpSendAsyncRequest function is called and the TPF_HTTP_KEEP_REQUEST option is not set, the high-speed connector cannot retry the operation if a synchronous timeout occurs after the request is sent and control is returned to the calling application ECB. In this case, a timeout error is returned to the application in the new ECB.

Group connect timeout
Specifies the maximum amount of time that the z/TPF system can wait for the endpoints in the group to establish connections to remote endpoints. The group connect timeout value is specified in the endpoint group descriptor file with the <groupConnectTimeout> element. The specified timeout includes the time the z/TPF system takes to establish the TCP connection and the time it takes to establish a TLS session if the specified value of the <TLS> element is YES. Specify a value in the range 10 - 120000 milliseconds. If you do not specify this element, the following timeouts are used:
  • TCP connection: 5 times of the value of the <syncTimeout> element
  • TLS session (if the <TLS> element is set to YES in the endpoint group descriptor file) : 1 second