BASEWLM and SERVERWLM display example
In the following Netstat VDPT/-O example, the weights represent normalized weights. That is, the original raw weights received from WLM are proportionally reduced for use by the distribution algorithm. Connections are distributed to these servers in a weighted, round-robin fashion using the normalized weights. In this example, the target server responsiveness (TSR) values are all 100, indicating that all servers are fully responsive to new connection requests. A value of 100 is also displayed for stacks that are at a level prior to z/OS® V1R7. In that case, no target server responsiveness calculations are applied to the WLM values.
The SERVERWLM parameter was not coded for DVIPA 201.2.10.11, port 245, so it is using WLM system weights.
MVS TCP/IP NETSTAT CS VxRx TCPIP NAME: TCPCS 12:19:18
Dynamic VIPA Distribution Port Table:
Dest IPaddr DPort DestXCF Addr Rdy TotalConn WLM TSR Flg
----------- ----- ------------ --- --------- --- --- ---
201.2.10.11 00245 201.1.10.10 001 0000000000 12 100 DB
201.2.10.11 00245 201.1.10.15 001 0000000000 04 100 B
201.2.10.12 04011 201.1.10.10 001 0000000000 04 100 S
201.2.10.12 04011 201.1.10.15 001 0000000000 08 100 S
201.2.10.12 04011 201.1.10.40 001 0000000000 16 100 SIf the BASEWLM parameter or the SERVERWLM parameter is specified and WLM weights are not available, incoming connections are distributed among all available servers using round-robin distribution.
Now consider the same example, as shown in the following Netstat VDPT/-O display, but with TSR values indicating that some of the servers are not accepting new connection setup requests productively. The displayed WLM weights have been modified by the TSR values:
MVS TCP/IP NETSTAT CS VxRx TCPIP NAME: TCPCS 12:19:18
Dynamic VIPA Distribution Port Table:
Dest IPaddr DPort DestXCF Addr Rdy TotalConn WLM TSR Flg
----------- ----- ------------ --- --------- --- --- ---
201.2.10.11 00245 201.1.10.10 001 0000000000 09 075 DB
201.2.10.11 00245 201.1.10.15 001 0000000000 04 100 B
201.2.10.12 04011 201.1.10.10 001 0000000000 03 090 S
201.2.10.12 04011 201.1.10.15 001 0000000000 06 075 S
201.2.10.12 04011 201.1.10.40 001 0000000000 03 020 SThe SERVERWLM parameter was coded for DVIPA 201.2.10.12, port 4011. For the server on destination 201.1.10.10, a TSR value of 90 indicates that the server is 90% responsive in accepting new connection requests. For the server on 201.1.10.15, a TSR value of 75 indicates that this server is 75% responsive in handling new connection requests. Likewise, for the server on 201.1.10.40, a TSR value of 20 indicates that it is only 20% effective in accepting new connection requests. These factors are used to modify the WLM server-specific weights, and the modified weights are normalized. As a result, the server on destination XCF 201.1.10.10 has a normalized WLM value of 3, the server on XCF 201.1.10.40 has a WLM value of 3, and the server on destination XCF 201.1.10.15 has a WLM value of 6. So, the server on destination XCF 201.1.10.15 is now favored over the other servers, and the server at 201.1.10.40 is now equal to the server at 201.1.10.10. Connections are distributed to these servers in a weighted, round-robin fashion using these normalized weights.
The SERVERWLM parameter was not coded for DVIPA 201.2.10.11 port 245, so it is using WLM system weights. The server at 201.1.10.10 has a TSR of 75, so the normalized weight is 9, three-quarters of what it was in the previous example. The server at 201.1.10.15 has a TSR of 100, so the normalized weight is the same as it was in the previous example.