Optimizing SQL Anywhere performance over a WAN

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　　You can do the following things to optimize performance over a WAN.

　　Set your timer values to an appropriately high level. Remember that the client and the server exchange packets to test for liveness and to determine if the query is complete yet. The switches to consider are:

-tr for active request termination timeouts. The server will only wait so long for a request to be retransmitted from the client before it will timeout the request and the connection. Increase this value if this problem is occurring in your setup. This switch is no longer necessary in Adaptive Server Anywhere 6.0

-ts for default client retry timeouts. This tells the client how long to wait for a response from the server before it resends the request. Increasing this value will cause fewer resends from the client which should reduce the amount of information passing between the client and server. If you increase this, you should also consider increasing the server request timeout period (see the -tr switch for the server). This switch is no longer necessary in Adaptive Server Anywhere 6.0

-tl for liveness checking. Increasing this value will not improve performance but you should increase this value if your connection keeps timing out due to liveness. The switch can be set at the client or the server. Any setting on the client will override the server setting for that particular client.

　　Consider using the -r parameter to disable multi-row fetching if you are only working with the first few rows in your result sets. This switch can be set by the server or by each individual client. It will cause the client to fetch only one row at a time instead of several.

　　Consider using the -b switch to limit the number of packets used in a multirecord fetch if you are retrieving a large number of rows.

　　Consider using the -s switch to increase the amount of buffer space used for network buffers.